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0efdf0fe | 1 | .. _bgp: |
42fc5d26 QY |
2 | |
3 | *** | |
4 | BGP | |
5 | *** | |
6 | ||
8fcedbd2 | 7 | :abbr:`BGP` stands for Border Gateway Protocol. The latest BGP version is 4. |
d1e7591e | 8 | BGP-4 is one of the Exterior Gateway Protocols and the de facto standard |
8fcedbd2 QY |
9 | interdomain routing protocol. BGP-4 is described in :rfc:`1771` and updated by |
10 | :rfc:`4271`. :rfc:`2858` adds multiprotocol support to BGP-4. | |
42fc5d26 | 11 | |
0efdf0fe | 12 | .. _starting-bgp: |
42fc5d26 QY |
13 | |
14 | Starting BGP | |
15 | ============ | |
16 | ||
8fcedbd2 QY |
17 | The default configuration file of *bgpd* is :file:`bgpd.conf`. *bgpd* searches |
18 | the current directory first, followed by |INSTALL_PREFIX_ETC|/bgpd.conf. All of | |
19 | *bgpd*'s commands must be configured in :file:`bgpd.conf` when the integrated | |
20 | config is not being used. | |
42fc5d26 | 21 | |
c1a54c05 | 22 | *bgpd* specific invocation options are described below. Common options may also |
0efdf0fe | 23 | be specified (:ref:`common-invocation-options`). |
42fc5d26 | 24 | |
c1a54c05 | 25 | .. program:: bgpd |
42fc5d26 | 26 | |
c9365894 | 27 | .. option:: -p, --bgp_port <port> |
42fc5d26 | 28 | |
db759bb0 | 29 | Set the bgp protocol's port number. When port number is 0, that means do not |
30 | listen bgp port. | |
42fc5d26 | 31 | |
c9365894 | 32 | .. option:: -l, --listenon |
42fc5d26 | 33 | |
d1aed873 | 34 | Specify specific IP addresses for bgpd to listen on, rather than its default |
c0868e8b | 35 | of ``0.0.0.0`` / ``::``. This can be useful to constrain bgpd to an internal |
d1aed873 AMR |
36 | address, or to run multiple bgpd processes on one host. Multiple addresses |
37 | can be specified. | |
38 | ||
39 | In the following example, bgpd is started listening for connections on the | |
40 | addresses 100.0.1.2 and fd00::2:2. The options -d (runs in daemon mode) and | |
41 | -f (uses specific configuration file) are also used in this example as we | |
42 | are likely to run multiple bgpd instances, each one with different | |
43 | configurations, when using -l option. | |
42fc5d26 | 44 | |
c17537f9 MBG |
45 | Note that this option implies the --no_kernel option, and no learned routes will be installed into the linux kernel. |
46 | ||
d1aed873 AMR |
47 | .. code-block:: shell |
48 | ||
49 | # /usr/lib/frr/bgpd -d -f /some-folder/bgpd.conf -l 100.0.1.2 -l fd00::2:2 | |
50 | ||
11a9a236 DS |
51 | .. option:: -n, --no_kernel |
52 | ||
53 | Do not install learned routes into the linux kernel. This option is useful | |
54 | for a route-reflector environment or if you are running multiple bgp | |
55 | processes in the same namespace. This option is different than the --no_zebra | |
56 | option in that a ZAPI connection is made. | |
57 | ||
8dad2243 DS |
58 | This option can also be toggled during runtime by using the |
59 | ``[no] bgp no-rib`` commands in VTY shell. | |
60 | ||
61 | Note that this option will persist after saving the configuration during | |
62 | runtime, unless unset by the ``no bgp no-rib`` command in VTY shell prior to | |
63 | a configuration write operation. | |
64 | ||
11a9a236 DS |
65 | .. option:: -S, --skip_runas |
66 | ||
67 | Skip the normal process of checking capabilities and changing user and group | |
68 | information. | |
69 | ||
70 | .. option:: -e, --ecmp | |
71 | ||
72 | Run BGP with a limited ecmp capability, that is different than what BGP | |
73 | was compiled with. The value specified must be greater than 0 and less | |
74 | than or equal to the MULTIPATH_NUM specified on compilation. | |
75 | ||
76 | .. option:: -Z, --no_zebra | |
77 | ||
78 | Do not communicate with zebra at all. This is different than the --no_kernel | |
79 | option in that we do not even open a ZAPI connection to the zebra process. | |
80 | ||
81 | .. option:: -s, --socket_size | |
82 | ||
83 | When opening tcp connections to our peers, set the socket send buffer | |
84 | size that the kernel will use for the peers socket. This option | |
85 | is only really useful at a very large scale. Experimentation should | |
86 | be done to see if this is helping or not at the scale you are running | |
87 | at. | |
88 | ||
89 | LABEL MANAGER | |
90 | ------------- | |
91 | ||
92 | .. option:: -I, --int_num | |
93 | ||
94 | Set zclient id. This is required when using Zebra label manager in proxy mode. | |
95 | ||
8fcedbd2 | 96 | .. _bgp-basic-concepts: |
42fc5d26 | 97 | |
8fcedbd2 QY |
98 | Basic Concepts |
99 | ============== | |
42fc5d26 | 100 | |
8fcedbd2 | 101 | .. _bgp-autonomous-systems: |
c3c5a71f | 102 | |
8fcedbd2 QY |
103 | Autonomous Systems |
104 | ------------------ | |
42fc5d26 | 105 | |
c0868e8b QY |
106 | From :rfc:`1930`: |
107 | ||
108 | An AS is a connected group of one or more IP prefixes run by one or more | |
109 | network operators which has a SINGLE and CLEARLY DEFINED routing policy. | |
110 | ||
111 | Each AS has an identifying number associated with it called an :abbr:`ASN | |
112 | (Autonomous System Number)`. This is a two octet value ranging in value from 1 | |
113 | to 65535. The AS numbers 64512 through 65535 are defined as private AS numbers. | |
114 | Private AS numbers must not be advertised on the global Internet. | |
115 | ||
116 | The :abbr:`ASN (Autonomous System Number)` is one of the essential elements of | |
8fcedbd2 | 117 | BGP. BGP is a distance vector routing protocol, and the AS-Path framework |
c0868e8b | 118 | provides distance vector metric and loop detection to BGP. |
42fc5d26 | 119 | |
c0868e8b | 120 | .. seealso:: :rfc:`1930` |
42fc5d26 | 121 | |
8fcedbd2 | 122 | .. _bgp-address-families: |
42fc5d26 | 123 | |
8fcedbd2 QY |
124 | Address Families |
125 | ---------------- | |
42fc5d26 | 126 | |
c0868e8b QY |
127 | Multiprotocol extensions enable BGP to carry routing information for multiple |
128 | network layer protocols. BGP supports an Address Family Identifier (AFI) for | |
129 | IPv4 and IPv6. Support is also provided for multiple sets of per-AFI | |
130 | information via the BGP Subsequent Address Family Identifier (SAFI). FRR | |
131 | supports SAFIs for unicast information, labeled information (:rfc:`3107` and | |
132 | :rfc:`8277`), and Layer 3 VPN information (:rfc:`4364` and :rfc:`4659`). | |
c3c5a71f | 133 | |
8fcedbd2 | 134 | .. _bgp-route-selection: |
42fc5d26 | 135 | |
8fcedbd2 QY |
136 | Route Selection |
137 | --------------- | |
42fc5d26 | 138 | |
8fcedbd2 QY |
139 | The route selection process used by FRR's BGP implementation uses the following |
140 | decision criterion, starting at the top of the list and going towards the | |
141 | bottom until one of the factors can be used. | |
42fc5d26 | 142 | |
8fcedbd2 | 143 | 1. **Weight check** |
42fc5d26 | 144 | |
c1a54c05 | 145 | Prefer higher local weight routes to lower routes. |
42fc5d26 | 146 | |
8fcedbd2 QY |
147 | 2. **Local preference check** |
148 | ||
c1a54c05 | 149 | Prefer higher local preference routes to lower. |
42fc5d26 | 150 | |
91e9aee0 DA |
151 | If ``bgp bestpath aigp`` is enabled, and both paths that are compared have |
152 | AIGP attribute, BGP uses AIGP tie-breaking unless both of the paths have the | |
153 | AIGP metric attribute. This means that the AIGP attribute is not evaluated | |
154 | during the best path selection process between two paths when one path does | |
155 | not have the AIGP attribute. | |
156 | ||
8fcedbd2 QY |
157 | 3. **Local route check** |
158 | ||
c1a54c05 | 159 | Prefer local routes (statics, aggregates, redistributed) to received routes. |
42fc5d26 | 160 | |
8fcedbd2 QY |
161 | 4. **AS path length check** |
162 | ||
c1a54c05 | 163 | Prefer shortest hop-count AS_PATHs. |
42fc5d26 | 164 | |
8fcedbd2 QY |
165 | 5. **Origin check** |
166 | ||
c1a54c05 QY |
167 | Prefer the lowest origin type route. That is, prefer IGP origin routes to |
168 | EGP, to Incomplete routes. | |
42fc5d26 | 169 | |
8fcedbd2 QY |
170 | 6. **MED check** |
171 | ||
c1a54c05 | 172 | Where routes with a MED were received from the same AS, prefer the route |
0efdf0fe | 173 | with the lowest MED. :ref:`bgp-med`. |
42fc5d26 | 174 | |
8fcedbd2 QY |
175 | 7. **External check** |
176 | ||
c1a54c05 QY |
177 | Prefer the route received from an external, eBGP peer over routes received |
178 | from other types of peers. | |
42fc5d26 | 179 | |
8fcedbd2 QY |
180 | 8. **IGP cost check** |
181 | ||
c1a54c05 | 182 | Prefer the route with the lower IGP cost. |
42fc5d26 | 183 | |
8fcedbd2 QY |
184 | 9. **Multi-path check** |
185 | ||
c1a54c05 QY |
186 | If multi-pathing is enabled, then check whether the routes not yet |
187 | distinguished in preference may be considered equal. If | |
9e146a81 | 188 | :clicmd:`bgp bestpath as-path multipath-relax` is set, all such routes are |
c1a54c05 QY |
189 | considered equal, otherwise routes received via iBGP with identical AS_PATHs |
190 | or routes received from eBGP neighbours in the same AS are considered equal. | |
42fc5d26 | 191 | |
8fcedbd2 QY |
192 | 10. **Already-selected external check** |
193 | ||
07738543 QY |
194 | Where both routes were received from eBGP peers, then prefer the route |
195 | which is already selected. Note that this check is not applied if | |
196 | :clicmd:`bgp bestpath compare-routerid` is configured. This check can | |
197 | prevent some cases of oscillation. | |
198 | ||
8fcedbd2 QY |
199 | 11. **Router-ID check** |
200 | ||
07738543 QY |
201 | Prefer the route with the lowest `router-ID`. If the route has an |
202 | `ORIGINATOR_ID` attribute, through iBGP reflection, then that router ID is | |
203 | used, otherwise the `router-ID` of the peer the route was received from is | |
204 | used. | |
205 | ||
8fcedbd2 QY |
206 | 12. **Cluster-List length check** |
207 | ||
07738543 QY |
208 | The route with the shortest cluster-list length is used. The cluster-list |
209 | reflects the iBGP reflection path the route has taken. | |
210 | ||
8fcedbd2 QY |
211 | 13. **Peer address** |
212 | ||
07738543 QY |
213 | Prefer the route received from the peer with the higher transport layer |
214 | address, as a last-resort tie-breaker. | |
42fc5d26 | 215 | |
8fcedbd2 QY |
216 | .. _bgp-capability-negotiation: |
217 | ||
218 | Capability Negotiation | |
219 | ---------------------- | |
220 | ||
221 | When adding IPv6 routing information exchange feature to BGP. There were some | |
222 | proposals. :abbr:`IETF (Internet Engineering Task Force)` | |
223 | :abbr:`IDR (Inter Domain Routing)` adopted a proposal called Multiprotocol | |
224 | Extension for BGP. The specification is described in :rfc:`2283`. The protocol | |
225 | does not define new protocols. It defines new attributes to existing BGP. When | |
226 | it is used exchanging IPv6 routing information it is called BGP-4+. When it is | |
227 | used for exchanging multicast routing information it is called MBGP. | |
228 | ||
229 | *bgpd* supports Multiprotocol Extension for BGP. So if a remote peer supports | |
230 | the protocol, *bgpd* can exchange IPv6 and/or multicast routing information. | |
231 | ||
232 | Traditional BGP did not have the feature to detect a remote peer's | |
233 | capabilities, e.g. whether it can handle prefix types other than IPv4 unicast | |
234 | routes. This was a big problem using Multiprotocol Extension for BGP in an | |
235 | operational network. :rfc:`2842` adopted a feature called Capability | |
236 | Negotiation. *bgpd* use this Capability Negotiation to detect the remote peer's | |
237 | capabilities. If a peer is only configured as an IPv4 unicast neighbor, *bgpd* | |
238 | does not send these Capability Negotiation packets (at least not unless other | |
239 | optional BGP features require capability negotiation). | |
240 | ||
241 | By default, FRR will bring up peering with minimal common capability for the | |
242 | both sides. For example, if the local router has unicast and multicast | |
243 | capabilities and the remote router only has unicast capability the local router | |
244 | will establish the connection with unicast only capability. When there are no | |
245 | common capabilities, FRR sends Unsupported Capability error and then resets the | |
246 | connection. | |
247 | ||
8fcedbd2 QY |
248 | .. _bgp-router-configuration: |
249 | ||
250 | BGP Router Configuration | |
251 | ======================== | |
252 | ||
253 | ASN and Router ID | |
254 | ----------------- | |
255 | ||
256 | First of all you must configure BGP router with the :clicmd:`router bgp ASN` | |
257 | command. The AS number is an identifier for the autonomous system. The BGP | |
258 | protocol uses the AS number for detecting whether the BGP connection is | |
259 | internal or external. | |
260 | ||
8fcedbd2 QY |
261 | .. clicmd:: router bgp ASN |
262 | ||
263 | Enable a BGP protocol process with the specified ASN. After | |
264 | this statement you can input any `BGP Commands`. | |
265 | ||
8fcedbd2 QY |
266 | .. clicmd:: bgp router-id A.B.C.D |
267 | ||
268 | This command specifies the router-ID. If *bgpd* connects to *zebra* it gets | |
269 | interface and address information. In that case default router ID value is | |
270 | selected as the largest IP Address of the interfaces. When `router zebra` is | |
271 | not enabled *bgpd* can't get interface information so `router-id` is set to | |
272 | 0.0.0.0. So please set router-id by hand. | |
273 | ||
c8a5e5e1 QY |
274 | |
275 | .. _bgp-multiple-autonomous-systems: | |
276 | ||
277 | Multiple Autonomous Systems | |
278 | --------------------------- | |
279 | ||
280 | FRR's BGP implementation is capable of running multiple autonomous systems at | |
281 | once. Each configured AS corresponds to a :ref:`zebra-vrf`. In the past, to get | |
282 | the same functionality the network administrator had to run a new *bgpd* | |
283 | process; using VRFs allows multiple autonomous systems to be handled in a | |
284 | single process. | |
285 | ||
286 | When using multiple autonomous systems, all router config blocks after the | |
287 | first one must specify a VRF to be the target of BGP's route selection. This | |
288 | VRF must be unique within respect to all other VRFs being used for the same | |
289 | purpose, i.e. two different autonomous systems cannot use the same VRF. | |
290 | However, the same AS can be used with different VRFs. | |
291 | ||
292 | .. note:: | |
293 | ||
294 | The separated nature of VRFs makes it possible to peer a single *bgpd* | |
edde3ce9 QY |
295 | process to itself, on one machine. Note that this can be done fully within |
296 | BGP without a corresponding VRF in the kernel or Zebra, which enables some | |
297 | practical use cases such as :ref:`route reflectors <bgp-route-reflector>` | |
298 | and route servers. | |
c8a5e5e1 QY |
299 | |
300 | Configuration of additional autonomous systems, or of a router that targets a | |
301 | specific VRF, is accomplished with the following command: | |
302 | ||
c8a5e5e1 QY |
303 | .. clicmd:: router bgp ASN vrf VRFNAME |
304 | ||
305 | ``VRFNAME`` is matched against VRFs configured in the kernel. When ``vrf | |
306 | VRFNAME`` is not specified, the BGP protocol process belongs to the default | |
307 | VRF. | |
308 | ||
309 | An example configuration with multiple autonomous systems might look like this: | |
310 | ||
311 | .. code-block:: frr | |
312 | ||
313 | router bgp 1 | |
314 | neighbor 10.0.0.1 remote-as 20 | |
315 | neighbor 10.0.0.2 remote-as 30 | |
316 | ! | |
317 | router bgp 2 vrf blue | |
318 | neighbor 10.0.0.3 remote-as 40 | |
319 | neighbor 10.0.0.4 remote-as 50 | |
320 | ! | |
321 | router bgp 3 vrf red | |
322 | neighbor 10.0.0.5 remote-as 60 | |
323 | neighbor 10.0.0.6 remote-as 70 | |
324 | ... | |
325 | ||
c8a5e5e1 QY |
326 | .. seealso:: :ref:`bgp-vrf-route-leaking` |
327 | .. seealso:: :ref:`zebra-vrf` | |
328 | ||
329 | ||
330 | .. _bgp-views: | |
331 | ||
332 | Views | |
333 | ----- | |
334 | ||
335 | In addition to supporting multiple autonomous systems, FRR's BGP implementation | |
336 | also supports *views*. | |
337 | ||
338 | BGP views are almost the same as normal BGP processes, except that routes | |
195c7461 QY |
339 | selected by BGP are not installed into the kernel routing table. Each BGP view |
340 | provides an independent set of routing information which is only distributed | |
341 | via BGP. Multiple views can be supported, and BGP view information is always | |
342 | independent from other routing protocols and Zebra/kernel routes. BGP views use | |
343 | the core instance (i.e., default VRF) for communication with peers. | |
edde3ce9 | 344 | |
c8a5e5e1 QY |
345 | .. clicmd:: router bgp AS-NUMBER view NAME |
346 | ||
347 | Make a new BGP view. You can use an arbitrary word for the ``NAME``. Routes | |
348 | selected by the view are not installed into the kernel routing table. | |
349 | ||
350 | With this command, you can setup Route Server like below. | |
351 | ||
352 | .. code-block:: frr | |
353 | ||
354 | ! | |
355 | router bgp 1 view 1 | |
356 | neighbor 10.0.0.1 remote-as 2 | |
357 | neighbor 10.0.0.2 remote-as 3 | |
358 | ! | |
359 | router bgp 2 view 2 | |
360 | neighbor 10.0.0.3 remote-as 4 | |
361 | neighbor 10.0.0.4 remote-as 5 | |
362 | ||
c8a5e5e1 QY |
363 | .. clicmd:: show [ip] bgp view NAME |
364 | ||
365 | Display the routing table of BGP view ``NAME``. | |
366 | ||
367 | ||
8fcedbd2 QY |
368 | Route Selection |
369 | --------------- | |
c3c5a71f | 370 | |
29adcd50 | 371 | .. clicmd:: bgp bestpath as-path confed |
42fc5d26 | 372 | |
c1a54c05 QY |
373 | This command specifies that the length of confederation path sets and |
374 | sequences should should be taken into account during the BGP best path | |
375 | decision process. | |
42fc5d26 | 376 | |
29adcd50 | 377 | .. clicmd:: bgp bestpath as-path multipath-relax |
42fc5d26 | 378 | |
c1a54c05 QY |
379 | This command specifies that BGP decision process should consider paths |
380 | of equal AS_PATH length candidates for multipath computation. Without | |
381 | the knob, the entire AS_PATH must match for multipath computation. | |
c3c5a71f | 382 | |
29adcd50 | 383 | .. clicmd:: bgp bestpath compare-routerid |
42fc5d26 | 384 | |
c1a54c05 QY |
385 | Ensure that when comparing routes where both are equal on most metrics, |
386 | including local-pref, AS_PATH length, IGP cost, MED, that the tie is broken | |
387 | based on router-ID. | |
42fc5d26 | 388 | |
c1a54c05 QY |
389 | If this option is enabled, then the already-selected check, where |
390 | already selected eBGP routes are preferred, is skipped. | |
42fc5d26 | 391 | |
c1a54c05 QY |
392 | If a route has an `ORIGINATOR_ID` attribute because it has been reflected, |
393 | that `ORIGINATOR_ID` will be used. Otherwise, the router-ID of the peer the | |
394 | route was received from will be used. | |
42fc5d26 | 395 | |
c1a54c05 QY |
396 | The advantage of this is that the route-selection (at this point) will be |
397 | more deterministic. The disadvantage is that a few or even one lowest-ID | |
d1e7591e | 398 | router may attract all traffic to otherwise-equal paths because of this |
c1a54c05 QY |
399 | check. It may increase the possibility of MED or IGP oscillation, unless |
400 | other measures were taken to avoid these. The exact behaviour will be | |
401 | sensitive to the iBGP and reflection topology. | |
42fc5d26 | 402 | |
ee88563a JM |
403 | .. clicmd:: bgp bestpath peer-type multipath-relax |
404 | ||
405 | This command specifies that BGP decision process should consider paths | |
406 | from all peers for multipath computation. If this option is enabled, | |
407 | paths learned from any of eBGP, iBGP, or confederation neighbors will | |
408 | be multipath if they are otherwise considered equal cost. | |
409 | ||
91e9aee0 DA |
410 | .. clicmd:: bgp bestpath aigp |
411 | ||
412 | Use the bgp bestpath aigp command to evaluate the AIGP attribute during | |
413 | the best path selection process between two paths that have the AIGP | |
414 | attribute. | |
415 | ||
416 | When bgp bestpath aigp is disabled, BGP does not use AIGP tie-breaking | |
417 | rules unless paths have the AIGP attribute. | |
418 | ||
419 | Disabled by default. | |
420 | ||
4a09f22f DS |
421 | .. clicmd:: maximum-paths (1-128) |
422 | ||
423 | Sets the maximum-paths value used for ecmp calculations for this | |
424 | bgp instance in EBGP. The maximum value listed, 128, can be limited by | |
425 | the ecmp cli for bgp or if the daemon was compiled with a lower | |
426 | ecmp value. This value can also be set in ipv4/ipv6 unicast/labeled | |
427 | unicast to only affect those particular afi/safi's. | |
428 | ||
429 | .. clicmd:: maximum-paths ibgp (1-128) [equal-cluster-length] | |
430 | ||
431 | Sets the maximum-paths value used for ecmp calculations for this | |
432 | bgp instance in IBGP. The maximum value listed, 128, can be limited by | |
433 | the ecmp cli for bgp or if the daemon was compiled with a lower | |
434 | ecmp value. This value can also be set in ipv4/ipv6 unicast/labeled | |
435 | unicast to only affect those particular afi/safi's. | |
436 | ||
8fcedbd2 QY |
437 | .. _bgp-distance: |
438 | ||
439 | Administrative Distance Metrics | |
440 | ------------------------------- | |
441 | ||
8fcedbd2 QY |
442 | .. clicmd:: distance bgp (1-255) (1-255) (1-255) |
443 | ||
f563acec TS |
444 | This command changes distance value of BGP. The arguments are the distance |
445 | values for external routes, internal routes and local routes | |
8fcedbd2 QY |
446 | respectively. |
447 | ||
8fcedbd2 QY |
448 | .. clicmd:: distance (1-255) A.B.C.D/M |
449 | ||
8fcedbd2 QY |
450 | .. clicmd:: distance (1-255) A.B.C.D/M WORD |
451 | ||
452 | Sets the administrative distance for a particular route. | |
42fc5d26 | 453 | |
713c64dd DA |
454 | .. _bgp-requires-policy: |
455 | ||
456 | Require policy on EBGP | |
457 | ------------------------------- | |
458 | ||
03750f1e | 459 | .. clicmd:: bgp ebgp-requires-policy |
713c64dd | 460 | |
8955d9e5 | 461 | This command requires incoming and outgoing filters to be applied |
b56f274a DS |
462 | for eBGP sessions as part of RFC-8212 compliance. Without the incoming |
463 | filter, no routes will be accepted. Without the outgoing filter, no | |
464 | routes will be announced. | |
8955d9e5 | 465 | |
b56f274a DS |
466 | This is enabled by default for the traditional configuration and |
467 | turned off by default for datacenter configuration. | |
713c64dd | 468 | |
b3cbe765 DA |
469 | When you enable/disable this option you MUST clear the session. |
470 | ||
62c42b0e DA |
471 | When the incoming or outgoing filter is missing you will see |
472 | "(Policy)" sign under ``show bgp summary``: | |
473 | ||
474 | .. code-block:: frr | |
475 | ||
476 | exit1# show bgp summary | |
477 | ||
6cac2fcc | 478 | IPv4 Unicast Summary (VRF default): |
62c42b0e DA |
479 | BGP router identifier 10.10.10.1, local AS number 65001 vrf-id 0 |
480 | BGP table version 4 | |
481 | RIB entries 7, using 1344 bytes of memory | |
482 | Peers 2, using 43 KiB of memory | |
483 | ||
b8f950d2 | 484 | Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd PfxSnt Desc |
485 | 192.168.0.2 4 65002 8 10 0 0 0 00:03:09 5 (Policy) N/A | |
486 | fe80:1::2222 4 65002 9 11 0 0 0 00:03:09 (Policy) (Policy) N/A | |
62c42b0e | 487 | |
b56f274a DS |
488 | Additionally a `show bgp neighbor` command would indicate in the `For address family:` |
489 | block that: | |
490 | ||
491 | .. code-block:: frr | |
492 | ||
493 | exit1# show bgp neighbor | |
494 | ... | |
495 | For address family: IPv4 Unicast | |
496 | Update group 1, subgroup 1 | |
497 | Packet Queue length 0 | |
498 | Inbound soft reconfiguration allowed | |
499 | Community attribute sent to this neighbor(all) | |
500 | Inbound updates discarded due to missing policy | |
501 | Outbound updates discarded due to missing policy | |
502 | 0 accepted prefixes | |
503 | ||
f0c81afe | 504 | Reject routes with AS_SET or AS_CONFED_SET types |
5031d886 | 505 | ------------------------------------------------ |
f0c81afe | 506 | |
03750f1e | 507 | .. clicmd:: bgp reject-as-sets |
f0c81afe DA |
508 | |
509 | This command enables rejection of incoming and outgoing routes having AS_SET or AS_CONFED_SET type. | |
510 | ||
105227af DA |
511 | Suppress duplicate updates |
512 | -------------------------- | |
513 | ||
03750f1e | 514 | .. clicmd:: bgp suppress-duplicates |
105227af DA |
515 | |
516 | For example, BGP routers can generate multiple identical announcements with | |
517 | empty community attributes if stripped at egress. This is an undesired behavior. | |
518 | Suppress duplicate updates if the route actually not changed. | |
519 | Default: enabled. | |
520 | ||
1ae314be DA |
521 | Send Hard Reset CEASE Notification for Administrative Reset |
522 | ----------------------------------------------------------- | |
523 | ||
524 | .. clicmd:: bgp hard-administrative-reset | |
525 | ||
526 | Send Hard Reset CEASE Notification for 'Administrative Reset' events. | |
527 | ||
528 | When disabled, and Graceful Restart Notification capability is exchanged | |
529 | between the peers, Graceful Restart procedures apply, and routes will be | |
530 | retained. | |
531 | ||
532 | Enabled by default. | |
533 | ||
835e9c5d DA |
534 | Disable checking if nexthop is connected on EBGP sessions |
535 | --------------------------------------------------------- | |
536 | ||
03750f1e | 537 | .. clicmd:: bgp disable-ebgp-connected-route-check |
835e9c5d DA |
538 | |
539 | This command is used to disable the connection verification process for EBGP peering sessions | |
540 | that are reachable by a single hop but are configured on a loopback interface or otherwise | |
541 | configured with a non-directly connected IP address. | |
542 | ||
0efdf0fe | 543 | .. _bgp-route-flap-dampening: |
42fc5d26 | 544 | |
8fcedbd2 QY |
545 | Route Flap Dampening |
546 | -------------------- | |
42fc5d26 | 547 | |
a30fec23 | 548 | .. clicmd:: bgp dampening (1-45) (1-20000) (1-50000) (1-255) |
c1a54c05 | 549 | |
a5c1e103 | 550 | This command enables BGP route-flap dampening and specifies dampening parameters. |
42fc5d26 | 551 | |
c1a54c05 | 552 | half-life |
a5c1e103 | 553 | Half-life time for the penalty |
42fc5d26 | 554 | |
c1a54c05 | 555 | reuse-threshold |
a5c1e103 | 556 | Value to start reusing a route |
42fc5d26 | 557 | |
c1a54c05 | 558 | suppress-threshold |
a5c1e103 | 559 | Value to start suppressing a route |
42fc5d26 | 560 | |
c1a54c05 | 561 | max-suppress |
a5c1e103 | 562 | Maximum duration to suppress a stable route |
42fc5d26 | 563 | |
c1a54c05 | 564 | The route-flap damping algorithm is compatible with :rfc:`2439`. The use of |
a5c1e103 | 565 | this command is not recommended nowadays. |
42fc5d26 | 566 | |
319a7d06 DA |
567 | At the moment, route-flap dampening is not working per VRF and is working only |
568 | for IPv4 unicast and multicast. | |
569 | ||
c1a54c05 | 570 | .. seealso:: |
8fcedbd2 | 571 | https://www.ripe.net/publications/docs/ripe-378 |
42fc5d26 | 572 | |
0efdf0fe | 573 | .. _bgp-med: |
42fc5d26 | 574 | |
8fcedbd2 QY |
575 | Multi-Exit Discriminator |
576 | ------------------------ | |
42fc5d26 | 577 | |
8fcedbd2 | 578 | The BGP :abbr:`MED (Multi-Exit Discriminator)` attribute has properties which |
c1a54c05 QY |
579 | can cause subtle convergence problems in BGP. These properties and problems |
580 | have proven to be hard to understand, at least historically, and may still not | |
581 | be widely understood. The following attempts to collect together and present | |
582 | what is known about MED, to help operators and FRR users in designing and | |
583 | configuring their networks. | |
42fc5d26 | 584 | |
07a17e6d QY |
585 | The BGP :abbr:`MED` attribute is intended to allow one AS to indicate its |
586 | preferences for its ingress points to another AS. The MED attribute will not be | |
587 | propagated on to another AS by the receiving AS - it is 'non-transitive' in the | |
588 | BGP sense. | |
42fc5d26 | 589 | |
c1a54c05 QY |
590 | E.g., if AS X and AS Y have 2 different BGP peering points, then AS X might set |
591 | a MED of 100 on routes advertised at one and a MED of 200 at the other. When AS | |
592 | Y selects between otherwise equal routes to or via AS X, AS Y should prefer to | |
593 | take the path via the lower MED peering of 100 with AS X. Setting the MED | |
594 | allows an AS to influence the routing taken to it within another, neighbouring | |
595 | AS. | |
42fc5d26 QY |
596 | |
597 | In this use of MED it is not really meaningful to compare the MED value on | |
c1a54c05 QY |
598 | routes where the next AS on the paths differs. E.g., if AS Y also had a route |
599 | for some destination via AS Z in addition to the routes from AS X, and AS Z had | |
600 | also set a MED, it wouldn't make sense for AS Y to compare AS Z's MED values to | |
601 | those of AS X. The MED values have been set by different administrators, with | |
602 | different frames of reference. | |
42fc5d26 QY |
603 | |
604 | The default behaviour of BGP therefore is to not compare MED values across | |
dc1046f7 | 605 | routes received from different neighbouring ASes. In FRR this is done by |
c1a54c05 QY |
606 | comparing the neighbouring, left-most AS in the received AS_PATHs of the routes |
607 | and only comparing MED if those are the same. | |
608 | ||
609 | Unfortunately, this behaviour of MED, of sometimes being compared across routes | |
610 | and sometimes not, depending on the properties of those other routes, means MED | |
611 | can cause the order of preference over all the routes to be undefined. That is, | |
612 | given routes A, B, and C, if A is preferred to B, and B is preferred to C, then | |
613 | a well-defined order should mean the preference is transitive (in the sense of | |
013f9762 | 614 | orders [#med-transitivity-rant]_) and that A would be preferred to C. |
42fc5d26 | 615 | |
c3c5a71f QY |
616 | However, when MED is involved this need not be the case. With MED it is |
617 | possible that C is actually preferred over A. So A is preferred to B, B is | |
618 | preferred to C, but C is preferred to A. This can be true even where BGP | |
c1a54c05 QY |
619 | defines a deterministic 'most preferred' route out of the full set of A,B,C. |
620 | With MED, for any given set of routes there may be a deterministically | |
621 | preferred route, but there need not be any way to arrange them into any order | |
622 | of preference. With unmodified MED, the order of preference of routes literally | |
623 | becomes undefined. | |
42fc5d26 | 624 | |
c3c5a71f | 625 | That MED can induce non-transitive preferences over routes can cause issues. |
c1a54c05 QY |
626 | Firstly, it may be perceived to cause routing table churn locally at speakers; |
627 | secondly, and more seriously, it may cause routing instability in iBGP | |
628 | topologies, where sets of speakers continually oscillate between different | |
629 | paths. | |
42fc5d26 | 630 | |
c3c5a71f | 631 | The first issue arises from how speakers often implement routing decisions. |
c1a54c05 QY |
632 | Though BGP defines a selection process that will deterministically select the |
633 | same route as best at any given speaker, even with MED, that process requires | |
634 | evaluating all routes together. For performance and ease of implementation | |
635 | reasons, many implementations evaluate route preferences in a pair-wise fashion | |
636 | instead. Given there is no well-defined order when MED is involved, the best | |
637 | route that will be chosen becomes subject to implementation details, such as | |
638 | the order the routes are stored in. That may be (locally) non-deterministic, | |
639 | e.g.: it may be the order the routes were received in. | |
42fc5d26 QY |
640 | |
641 | This indeterminism may be considered undesirable, though it need not cause | |
c1a54c05 QY |
642 | problems. It may mean additional routing churn is perceived, as sometimes more |
643 | updates may be produced than at other times in reaction to some event . | |
42fc5d26 QY |
644 | |
645 | This first issue can be fixed with a more deterministic route selection that | |
c3c5a71f | 646 | ensures routes are ordered by the neighbouring AS during selection. |
9e146a81 | 647 | :clicmd:`bgp deterministic-med`. This may reduce the number of updates as routes |
c1a54c05 QY |
648 | are received, and may in some cases reduce routing churn. Though, it could |
649 | equally deterministically produce the largest possible set of updates in | |
650 | response to the most common sequence of received updates. | |
42fc5d26 QY |
651 | |
652 | A deterministic order of evaluation tends to imply an additional overhead of | |
c3c5a71f | 653 | sorting over any set of n routes to a destination. The implementation of |
dc1046f7 | 654 | deterministic MED in FRR scales significantly worse than most sorting |
c1a54c05 QY |
655 | algorithms at present, with the number of paths to a given destination. That |
656 | number is often low enough to not cause any issues, but where there are many | |
657 | paths, the deterministic comparison may quickly become increasingly expensive | |
658 | in terms of CPU. | |
659 | ||
660 | Deterministic local evaluation can *not* fix the second, more major, issue of | |
661 | MED however. Which is that the non-transitive preference of routes MED can | |
662 | cause may lead to routing instability or oscillation across multiple speakers | |
663 | in iBGP topologies. This can occur with full-mesh iBGP, but is particularly | |
664 | problematic in non-full-mesh iBGP topologies that further reduce the routing | |
665 | information known to each speaker. This has primarily been documented with iBGP | |
749afd7d RF |
666 | :ref:`route-reflection <bgp-route-reflector>` topologies. However, any |
667 | route-hiding technologies potentially could also exacerbate oscillation with MED. | |
c1a54c05 QY |
668 | |
669 | This second issue occurs where speakers each have only a subset of routes, and | |
670 | there are cycles in the preferences between different combinations of routes - | |
671 | as the undefined order of preference of MED allows - and the routes are | |
672 | distributed in a way that causes the BGP speakers to 'chase' those cycles. This | |
673 | can occur even if all speakers use a deterministic order of evaluation in route | |
674 | selection. | |
675 | ||
676 | E.g., speaker 4 in AS A might receive a route from speaker 2 in AS X, and from | |
677 | speaker 3 in AS Y; while speaker 5 in AS A might receive that route from | |
678 | speaker 1 in AS Y. AS Y might set a MED of 200 at speaker 1, and 100 at speaker | |
679 | 3. I.e, using ASN:ID:MED to label the speakers: | |
42fc5d26 QY |
680 | |
681 | :: | |
682 | ||
c1a54c05 QY |
683 | . |
684 | /---------------\\ | |
42fc5d26 | 685 | X:2------|--A:4-------A:5--|-Y:1:200 |
c1a54c05 QY |
686 | Y:3:100--|-/ | |
687 | \\---------------/ | |
c3c5a71f | 688 | |
42fc5d26 | 689 | |
42fc5d26 | 690 | |
c1a54c05 QY |
691 | Assuming all other metrics are equal (AS_PATH, ORIGIN, 0 IGP costs), then based |
692 | on the RFC4271 decision process speaker 4 will choose X:2 over Y:3:100, based | |
693 | on the lower ID of 2. Speaker 4 advertises X:2 to speaker 5. Speaker 5 will | |
694 | continue to prefer Y:1:200 based on the ID, and advertise this to speaker 4. | |
695 | Speaker 4 will now have the full set of routes, and the Y:1:200 it receives | |
696 | from 5 will beat X:2, but when speaker 4 compares Y:1:200 to Y:3:100 the MED | |
697 | check now becomes active as the ASes match, and now Y:3:100 is preferred. | |
698 | Speaker 4 therefore now advertises Y:3:100 to 5, which will also agrees that | |
699 | Y:3:100 is preferred to Y:1:200, and so withdraws the latter route from 4. | |
700 | Speaker 4 now has only X:2 and Y:3:100, and X:2 beats Y:3:100, and so speaker 4 | |
701 | implicitly updates its route to speaker 5 to X:2. Speaker 5 sees that Y:1:200 | |
702 | beats X:2 based on the ID, and advertises Y:1:200 to speaker 4, and the cycle | |
703 | continues. | |
42fc5d26 QY |
704 | |
705 | The root cause is the lack of a clear order of preference caused by how MED | |
706 | sometimes is and sometimes is not compared, leading to this cycle in the | |
707 | preferences between the routes: | |
708 | ||
709 | :: | |
710 | ||
c1a54c05 QY |
711 | . |
712 | /---> X:2 ---beats---> Y:3:100 --\\ | |
713 | | | | |
714 | | | | |
715 | \\---beats--- Y:1:200 <---beats---/ | |
c3c5a71f | 716 | |
42fc5d26 | 717 | |
42fc5d26 QY |
718 | |
719 | This particular type of oscillation in full-mesh iBGP topologies can be | |
720 | avoided by speakers preferring already selected, external routes rather than | |
c1a54c05 QY |
721 | choosing to update to new a route based on a post-MED metric (e.g. router-ID), |
722 | at the cost of a non-deterministic selection process. FRR implements this, as | |
723 | do many other implementations, so long as it is not overridden by setting | |
9e146a81 | 724 | :clicmd:`bgp bestpath compare-routerid`, and see also |
8fcedbd2 | 725 | :ref:`bgp-route-selection`. |
42fc5d26 QY |
726 | |
727 | However, more complex and insidious cycles of oscillation are possible with | |
c3c5a71f | 728 | iBGP route-reflection, which are not so easily avoided. These have been |
c1a54c05 QY |
729 | documented in various places. See, e.g.: |
730 | ||
731 | - [bgp-route-osci-cond]_ | |
732 | - [stable-flexible-ibgp]_ | |
733 | - [ibgp-correctness]_ | |
734 | ||
735 | for concrete examples and further references. | |
736 | ||
737 | There is as of this writing *no* known way to use MED for its original purpose; | |
738 | *and* reduce routing information in iBGP topologies; *and* be sure to avoid the | |
739 | instability problems of MED due the non-transitive routing preferences it can | |
740 | induce; in general on arbitrary networks. | |
741 | ||
742 | There may be iBGP topology specific ways to reduce the instability risks, even | |
743 | while using MED, e.g.: by constraining the reflection topology and by tuning | |
013f9762 | 744 | IGP costs between route-reflector clusters, see :rfc:`3345` for details. In the |
c1a54c05 QY |
745 | near future, the Add-Path extension to BGP may also solve MED oscillation while |
746 | still allowing MED to be used as intended, by distributing "best-paths per | |
747 | neighbour AS". This would be at the cost of distributing at least as many | |
748 | routes to all speakers as a full-mesh iBGP would, if not more, while also | |
749 | imposing similar CPU overheads as the "Deterministic MED" feature at each | |
750 | Add-Path reflector. | |
42fc5d26 QY |
751 | |
752 | More generally, the instability problems that MED can introduce on more | |
753 | complex, non-full-mesh, iBGP topologies may be avoided either by: | |
754 | ||
013f9762 | 755 | - Setting :clicmd:`bgp always-compare-med`, however this allows MED to be compared |
42fc5d26 QY |
756 | across values set by different neighbour ASes, which may not produce |
757 | coherent desirable results, of itself. | |
4b44467c | 758 | - Effectively ignoring MED by setting MED to the same value (e.g.: 0) using |
013f9762 QY |
759 | :clicmd:`set metric METRIC` on all received routes, in combination with |
760 | setting :clicmd:`bgp always-compare-med` on all speakers. This is the simplest | |
42fc5d26 QY |
761 | and most performant way to avoid MED oscillation issues, where an AS is happy |
762 | not to allow neighbours to inject this problematic metric. | |
763 | ||
42fc5d26 QY |
764 | As MED is evaluated after the AS_PATH length check, another possible use for |
765 | MED is for intra-AS steering of routes with equal AS_PATH length, as an | |
c1a54c05 QY |
766 | extension of the last case above. As MED is evaluated before IGP metric, this |
767 | can allow cold-potato routing to be implemented to send traffic to preferred | |
768 | hand-offs with neighbours, rather than the closest hand-off according to the | |
769 | IGP metric. | |
770 | ||
771 | Note that even if action is taken to address the MED non-transitivity issues, | |
772 | other oscillations may still be possible. E.g., on IGP cost if iBGP and IGP | |
773 | topologies are at cross-purposes with each other - see the Flavel and Roughan | |
774 | paper above for an example. Hence the guideline that the iBGP topology should | |
775 | follow the IGP topology. | |
776 | ||
29adcd50 | 777 | .. clicmd:: bgp deterministic-med |
42fc5d26 | 778 | |
c1a54c05 QY |
779 | Carry out route-selection in way that produces deterministic answers |
780 | locally, even in the face of MED and the lack of a well-defined order of | |
781 | preference it can induce on routes. Without this option the preferred route | |
782 | with MED may be determined largely by the order that routes were received | |
783 | in. | |
42fc5d26 | 784 | |
c1a54c05 QY |
785 | Setting this option will have a performance cost that may be noticeable when |
786 | there are many routes for each destination. Currently in FRR it is | |
787 | implemented in a way that scales poorly as the number of routes per | |
788 | destination increases. | |
42fc5d26 | 789 | |
c1a54c05 | 790 | The default is that this option is not set. |
42fc5d26 QY |
791 | |
792 | Note that there are other sources of indeterminism in the route selection | |
793 | process, specifically, the preference for older and already selected routes | |
8fcedbd2 | 794 | from eBGP peers, :ref:`bgp-route-selection`. |
42fc5d26 | 795 | |
29adcd50 | 796 | .. clicmd:: bgp always-compare-med |
42fc5d26 | 797 | |
c1a54c05 QY |
798 | Always compare the MED on routes, even when they were received from |
799 | different neighbouring ASes. Setting this option makes the order of | |
800 | preference of routes more defined, and should eliminate MED induced | |
801 | oscillations. | |
42fc5d26 | 802 | |
c1a54c05 | 803 | If using this option, it may also be desirable to use |
9e146a81 | 804 | :clicmd:`set metric METRIC` to set MED to 0 on routes received from external |
c1a54c05 | 805 | neighbours. |
42fc5d26 | 806 | |
9e146a81 QY |
807 | This option can be used, together with :clicmd:`set metric METRIC` to use |
808 | MED as an intra-AS metric to steer equal-length AS_PATH routes to, e.g., | |
809 | desired exit points. | |
42fc5d26 | 810 | |
efcb2ebb | 811 | |
812 | .. _bgp-graceful-restart: | |
813 | ||
814 | Graceful Restart | |
815 | ---------------- | |
816 | ||
817 | BGP graceful restart functionality as defined in | |
818 | `RFC-4724 <https://tools.ietf.org/html/rfc4724/>`_ defines the mechanisms that | |
819 | allows BGP speaker to continue to forward data packets along known routes | |
820 | while the routing protocol information is being restored. | |
821 | ||
822 | ||
823 | Usually, when BGP on a router restarts, all the BGP peers detect that the | |
824 | session went down and then came up. This "down/up" transition results in a | |
825 | "routing flap" and causes BGP route re-computation, generation of BGP routing | |
826 | updates, and unnecessary churn to the forwarding tables. | |
827 | ||
828 | The following functionality is provided by graceful restart: | |
829 | ||
830 | 1. The feature allows the restarting router to indicate to the helping peer the | |
831 | routes it can preserve in its forwarding plane during control plane restart | |
832 | by sending graceful restart capability in the OPEN message sent during | |
833 | session establishment. | |
834 | 2. The feature allows helping router to advertise to all other peers the routes | |
835 | received from the restarting router which are preserved in the forwarding | |
836 | plane of the restarting router during control plane restart. | |
837 | ||
838 | ||
839 | :: | |
840 | ||
841 | ||
842 | ||
843 | (R1)-----------------------------------------------------------------(R2) | |
844 | ||
845 | 1. BGP Graceful Restart Capability exchanged between R1 & R2. | |
846 | ||
847 | <---------------------------------------------------------------------> | |
848 | ||
849 | 2. Kill BGP Process at R1. | |
850 | ||
851 | ----------------------------------------------------------------------> | |
852 | ||
853 | 3. R2 Detects the above BGP Restart & verifies BGP Restarting | |
854 | Capability of R1. | |
855 | ||
856 | 4. Start BGP Process at R1. | |
857 | ||
858 | 5. Re-establish the BGP session between R1 & R2. | |
859 | ||
860 | <---------------------------------------------------------------------> | |
861 | ||
862 | 6. R2 Send initial route updates, followed by End-Of-Rib. | |
863 | ||
864 | <---------------------------------------------------------------------- | |
865 | ||
866 | 7. R1 was waiting for End-Of-Rib from R2 & which has been received | |
867 | now. | |
868 | ||
869 | 8. R1 now runs BGP Best-Path algorithm. Send Initial BGP Update, | |
870 | followed by End-Of Rib | |
871 | ||
872 | <---------------------------------------------------------------------> | |
873 | ||
874 | ||
4907bcd8 | 875 | .. _bgp-GR-preserve-forwarding-state: |
876 | ||
877 | BGP-GR Preserve-Forwarding State | |
878 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | |
879 | ||
880 | BGP OPEN message carrying optional capabilities for Graceful Restart has | |
881 | 8 bit “Flags for Address Family” for given AFI and SAFI. This field contains | |
882 | bit flags relating to routes that were advertised with the given AFI and SAFI. | |
883 | ||
884 | .. code-block:: frr | |
885 | ||
886 | 0 1 2 3 4 5 6 7 | |
887 | +-+-+-+-+-+-+-+-+ | |
888 | |F| Reserved | | |
889 | +-+-+-+-+-+-+-+-+ | |
890 | ||
891 | The most significant bit is defined as the Forwarding State (F) bit, which | |
892 | can be used to indicate whether the forwarding state for routes that were | |
893 | advertised with the given AFI and SAFI has indeed been preserved during the | |
894 | previous BGP restart. When set (value 1), the bit indicates that the | |
895 | forwarding state has been preserved. | |
896 | The remaining bits are reserved and MUST be set to zero by the sender and | |
897 | ignored by the receiver. | |
898 | ||
4907bcd8 | 899 | .. clicmd:: bgp graceful-restart preserve-fw-state |
900 | ||
901 | FRR gives us the option to enable/disable the "F" flag using this specific | |
902 | vty command. However, it doesn't have the option to enable/disable | |
903 | this flag only for specific AFI/SAFI i.e. when this command is used, it | |
904 | applied to all the supported AFI/SAFI combinations for this peer. | |
905 | ||
efcb2ebb | 906 | .. _bgp-end-of-rib-message: |
907 | ||
908 | End-of-RIB (EOR) message | |
909 | ^^^^^^^^^^^^^^^^^^^^^^^^ | |
910 | ||
911 | An UPDATE message with no reachable Network Layer Reachability Information | |
912 | (NLRI) and empty withdrawn NLRI is specified as the End-of-RIB marker that can | |
913 | be used by a BGP speaker to indicate to its peer the completion of the initial | |
914 | routing update after the session is established. | |
915 | ||
916 | For the IPv4 unicast address family, the End-of-RIB marker is an UPDATE message | |
917 | with the minimum length. For any other address family, it is an UPDATE message | |
918 | that contains only the MP_UNREACH_NLRI attribute with no withdrawn routes for | |
919 | that <AFI, SAFI>. | |
920 | ||
921 | Although the End-of-RIB marker is specified for the purpose of BGP graceful | |
922 | restart, it is noted that the generation of such a marker upon completion of | |
923 | the initial update would be useful for routing convergence in general, and thus | |
924 | the practice is recommended. | |
925 | ||
926 | .. _bgp-route-selection-deferral-timer: | |
927 | ||
928 | Route Selection Deferral Timer | |
929 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | |
930 | ||
931 | Specifies the time the restarting router defers the route selection process | |
932 | after restart. | |
933 | ||
934 | Restarting Router : The usage of route election deferral timer is specified | |
935 | in https://tools.ietf.org/html/rfc4724#section-4.1 | |
936 | ||
937 | Once the session between the Restarting Speaker and the Receiving Speaker is | |
938 | re-established, the Restarting Speaker will receive and process BGP messages | |
939 | from its peers. | |
940 | ||
941 | However, it MUST defer route selection for an address family until it either. | |
942 | ||
943 | 1. Receives the End-of-RIB marker from all its peers (excluding the ones with | |
944 | the "Restart State" bit set in the received capability and excluding the ones | |
945 | that do not advertise the graceful restart capability). | |
946 | 2. The Selection_Deferral_Timer timeout. | |
947 | ||
efcb2ebb | 948 | .. clicmd:: bgp graceful-restart select-defer-time (0-3600) |
949 | ||
950 | This is command, will set deferral time to value specified. | |
951 | ||
952 | ||
efcb2ebb | 953 | .. clicmd:: bgp graceful-restart rib-stale-time (1-3600) |
954 | ||
955 | This is command, will set the time for which stale routes are kept in RIB. | |
956 | ||
dcbebfd3 DA |
957 | .. clicmd:: bgp graceful-restart restart-time (0-4095) |
958 | ||
959 | Set the time to wait to delete stale routes before a BGP open message | |
960 | is received. | |
961 | ||
962 | Using with Long-lived Graceful Restart capability, this is recommended | |
963 | setting this timer to 0 and control stale routes with | |
964 | ``bgp long-lived-graceful-restart stale-time``. | |
965 | ||
966 | Default value is 120. | |
967 | ||
2b3de9e5 DA |
968 | .. clicmd:: bgp graceful-restart stalepath-time (1-4095) |
969 | ||
970 | This is command, will set the max time (in seconds) to hold onto | |
971 | restarting peer's stale paths. | |
972 | ||
973 | It also controls Enhanced Route-Refresh timer. | |
974 | ||
975 | If this command is configured and the router does not receive a Route-Refresh EoRR | |
976 | message, the router removes the stale routes from the BGP table after the timer | |
977 | expires. The stale path timer is started when the router receives a Route-Refresh | |
978 | BoRR message. | |
979 | ||
f2ca5c5b DA |
980 | .. clicmd:: bgp graceful-restart notification |
981 | ||
982 | Indicate Graceful Restart support for BGP NOTIFICATION messages. | |
983 | ||
984 | After changing this parameter, you have to reset the peers in order to advertise | |
985 | N-bit in Graceful Restart capability. | |
986 | ||
19f98055 DA |
987 | Without Graceful-Restart Notification capability (N-bit not set), GR is not |
988 | activated when receiving CEASE/HOLDTIME expire notifications. | |
989 | ||
990 | When sending ``CEASE/Administrative Reset`` (``clear bgp``), the session is closed | |
991 | and routes are not retained. When N-bit is set and ``bgp hard-administrative-reset`` | |
992 | is turned off Graceful-Restart is activated and routes are retained. | |
993 | ||
f2ca5c5b DA |
994 | Enabled by default. |
995 | ||
efcb2ebb | 996 | .. _bgp-per-peer-graceful-restart: |
997 | ||
998 | BGP Per Peer Graceful Restart | |
999 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | |
1000 | ||
1001 | Ability to enable and disable graceful restart, helper and no GR at all mode | |
1002 | functionality at peer level. | |
1003 | ||
1004 | So bgp graceful restart can be enabled at modes global BGP level or at per | |
1005 | peer level. There are two FSM, one for BGP GR global mode and other for peer | |
1006 | per GR. | |
1007 | ||
1008 | Default global mode is helper and default peer per mode is inherit from global. | |
1009 | If per peer mode is configured, the GR mode of this particular peer will | |
1010 | override the global mode. | |
1011 | ||
2ba1fe69 | 1012 | .. _bgp-GR-global-mode-cmd: |
efcb2ebb | 1013 | |
1014 | BGP GR Global Mode Commands | |
1015 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^ | |
1016 | ||
efcb2ebb | 1017 | .. clicmd:: bgp graceful-restart |
1018 | ||
f563acec | 1019 | This command will enable BGP graceful restart functionality at the global |
efcb2ebb | 1020 | level. |
1021 | ||
efcb2ebb | 1022 | .. clicmd:: bgp graceful-restart disable |
1023 | ||
1024 | This command will disable both the functionality graceful restart and helper | |
1025 | mode. | |
1026 | ||
1027 | ||
1028 | .. _bgp-GR-peer-mode-cmd: | |
1029 | ||
1030 | BGP GR Peer Mode Commands | |
1031 | ^^^^^^^^^^^^^^^^^^^^^^^^^ | |
1032 | ||
efcb2ebb | 1033 | .. clicmd:: neighbor A.B.C.D graceful-restart |
1034 | ||
f563acec | 1035 | This command will enable BGP graceful restart functionality at the peer |
efcb2ebb | 1036 | level. |
1037 | ||
efcb2ebb | 1038 | .. clicmd:: neighbor A.B.C.D graceful-restart-helper |
1039 | ||
1040 | This command will enable BGP graceful restart helper only functionality | |
1041 | at the peer level. | |
1042 | ||
efcb2ebb | 1043 | .. clicmd:: neighbor A.B.C.D graceful-restart-disable |
1044 | ||
1045 | This command will disable the entire BGP graceful restart functionality | |
1046 | at the peer level. | |
1047 | ||
1048 | ||
8606be87 DA |
1049 | Long-lived Graceful Restart |
1050 | --------------------------- | |
1051 | ||
1052 | Currently, only restarter mode is supported. This capability is advertised only | |
1053 | if graceful restart capability is negotiated. | |
1054 | ||
5970204c | 1055 | .. clicmd:: bgp long-lived-graceful-restart stale-time (1-16777215) |
8606be87 DA |
1056 | |
1057 | Specifies the maximum time to wait before purging long-lived stale routes for | |
1058 | helper routers. | |
1059 | ||
7f8a9a24 DA |
1060 | Default is 0, which means the feature is off by default. Only graceful |
1061 | restart takes into account. | |
8606be87 | 1062 | |
df465afe DS |
1063 | .. _bgp-shutdown: |
1064 | ||
1065 | Administrative Shutdown | |
1066 | ----------------------- | |
1067 | ||
03750f1e | 1068 | .. clicmd:: bgp shutdown [message MSG...] |
df465afe DS |
1069 | |
1070 | Administrative shutdown of all peers of a bgp instance. Drop all BGP peers, | |
1071 | but preserve their configurations. The peers are notified in accordance with | |
1072 | `RFC 8203 <https://tools.ietf.org/html/rfc8203/>`_ by sending a | |
1073 | ``NOTIFICATION`` message with error code ``Cease`` and subcode | |
1074 | ``Administrative Shutdown`` prior to terminating connections. This global | |
1075 | shutdown is independent of the neighbor shutdown, meaning that individually | |
1076 | shut down peers will not be affected by lifting it. | |
1077 | ||
1078 | An optional shutdown message `MSG` can be specified. | |
1079 | ||
1080 | ||
0efdf0fe | 1081 | .. _bgp-network: |
42fc5d26 | 1082 | |
8fcedbd2 QY |
1083 | Networks |
1084 | -------- | |
42fc5d26 | 1085 | |
c1a54c05 | 1086 | .. clicmd:: network A.B.C.D/M |
42fc5d26 | 1087 | |
9eb95b3b | 1088 | This command adds the announcement network. |
c3c5a71f | 1089 | |
9eb95b3b QY |
1090 | .. code-block:: frr |
1091 | ||
1092 | router bgp 1 | |
1093 | address-family ipv4 unicast | |
1094 | network 10.0.0.0/8 | |
1095 | exit-address-family | |
42fc5d26 | 1096 | |
c1a54c05 QY |
1097 | This configuration example says that network 10.0.0.0/8 will be |
1098 | announced to all neighbors. Some vendors' routers don't advertise | |
1099 | routes if they aren't present in their IGP routing tables; `bgpd` | |
1100 | doesn't care about IGP routes when announcing its routes. | |
c3c5a71f | 1101 | |
42fc5d26 | 1102 | |
03750f1e | 1103 | .. clicmd:: bgp network import-check |
f990a416 DS |
1104 | |
1105 | This configuration modifies the behavior of the network statement. | |
1106 | If you have this configured the underlying network must exist in | |
1107 | the rib. If you have the [no] form configured then BGP will not | |
1108 | check for the networks existence in the rib. For versions 7.3 and | |
1109 | before frr defaults for datacenter were the network must exist, | |
1110 | traditional did not check for existence. For versions 7.4 and beyond | |
1111 | both traditional and datacenter the network must exist. | |
1112 | ||
ef1b6319 | 1113 | .. _bgp-ipv6-support: |
547ba033 MH |
1114 | |
1115 | IPv6 Support | |
1116 | ------------ | |
1117 | ||
03750f1e | 1118 | .. clicmd:: neighbor A.B.C.D activate |
547ba033 | 1119 | |
ef1b6319 | 1120 | This configuration modifies whether to enable an address family for a |
547ba033 MH |
1121 | specific neighbor. By default only the IPv4 unicast address family is |
1122 | enabled. | |
1123 | ||
1124 | .. code-block:: frr | |
1125 | ||
1126 | router bgp 1 | |
1127 | address-family ipv6 unicast | |
1128 | neighbor 2001:0DB8::1 activate | |
1129 | network 2001:0DB8:5009::/64 | |
1130 | exit-address-family | |
1131 | ||
1132 | This configuration example says that network 2001:0DB8:5009::/64 will be | |
1133 | announced and enables the neighbor 2001:0DB8::1 to receive this announcement. | |
1134 | ||
547ba033 MH |
1135 | By default, only the IPv4 unicast address family is announced to all |
1136 | neighbors. Using the 'no bgp default ipv4-unicast' configuration overrides | |
1137 | this default so that all address families need to be enabled explicitly. | |
1138 | ||
1139 | .. code-block:: frr | |
1140 | ||
1141 | router bgp 1 | |
1142 | no bgp default ipv4-unicast | |
1143 | neighbor 10.10.10.1 remote-as 2 | |
1144 | neighbor 2001:0DB8::1 remote-as 3 | |
1145 | address-family ipv4 unicast | |
1146 | neighbor 10.10.10.1 activate | |
1147 | network 192.168.1.0/24 | |
1148 | exit-address-family | |
1149 | address-family ipv6 unicast | |
1150 | neighbor 2001:0DB8::1 activate | |
1151 | network 2001:0DB8:5009::/64 | |
1152 | exit-address-family | |
1153 | ||
1154 | This configuration demonstrates how the 'no bgp default ipv4-unicast' might | |
1155 | be used in a setup with two upstreams where each of the upstreams should only | |
f563acec | 1156 | receive either IPv4 or IPv6 announcements. |
547ba033 | 1157 | |
2c853e5e DA |
1158 | Using the ``bgp default ipv6-unicast`` configuration, IPv6 unicast |
1159 | address family is enabled by default for all new neighbors. | |
1160 | ||
547ba033 | 1161 | |
8fcedbd2 | 1162 | .. _bgp-route-aggregation: |
42fc5d26 QY |
1163 | |
1164 | Route Aggregation | |
1165 | ----------------- | |
1166 | ||
5101fece | 1167 | .. _bgp-route-aggregation-ipv4: |
1168 | ||
1169 | Route Aggregation-IPv4 Address Family | |
1170 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | |
1171 | ||
c1a54c05 | 1172 | .. clicmd:: aggregate-address A.B.C.D/M |
c3c5a71f | 1173 | |
c1a54c05 | 1174 | This command specifies an aggregate address. |
42fc5d26 | 1175 | |
9a339b7f DA |
1176 | In order to advertise an aggregated prefix, a more specific (longer) prefix |
1177 | MUST exist in the BGP table. For example, if you want to create an | |
1178 | ``aggregate-address 10.0.0.0/24``, you should make sure you have something | |
1179 | like ``10.0.0.5/32`` or ``10.0.0.0/26``, or any other smaller prefix in the | |
1180 | BGP table. The routing information table (RIB) is not enough, you have to | |
1181 | redistribute them into the BGP table. | |
1182 | ||
ac2201bb DA |
1183 | .. clicmd:: aggregate-address A.B.C.D/M route-map NAME |
1184 | ||
1185 | Apply a route-map for an aggregated prefix. | |
1186 | ||
a87d2ef7 DA |
1187 | .. clicmd:: aggregate-address A.B.C.D/M origin <egp|igp|incomplete> |
1188 | ||
1189 | Override ORIGIN for an aggregated prefix. | |
1190 | ||
c1a54c05 | 1191 | .. clicmd:: aggregate-address A.B.C.D/M as-set |
42fc5d26 | 1192 | |
c1a54c05 QY |
1193 | This command specifies an aggregate address. Resulting routes include |
1194 | AS set. | |
42fc5d26 | 1195 | |
c1a54c05 | 1196 | .. clicmd:: aggregate-address A.B.C.D/M summary-only |
c3c5a71f | 1197 | |
9a339b7f DA |
1198 | This command specifies an aggregate address. |
1199 | ||
1200 | Longer prefixes advertisements of more specific routes to all neighbors are suppressed. | |
42fc5d26 | 1201 | |
01338ba1 RZ |
1202 | .. clicmd:: aggregate-address A.B.C.D/M matching-MED-only |
1203 | ||
1204 | Configure the aggregated address to only be created when the routes MED | |
1205 | match, otherwise no aggregated route will be created. | |
1206 | ||
8fbb9c95 RZ |
1207 | .. clicmd:: aggregate-address A.B.C.D/M suppress-map NAME |
1208 | ||
1209 | Similar to `summary-only`, but will only suppress more specific routes that | |
1210 | are matched by the selected route-map. | |
1211 | ||
ac2201bb | 1212 | |
03750f1e QY |
1213 | This configuration example sets up an ``aggregate-address`` under the ipv4 |
1214 | address-family. | |
5101fece | 1215 | |
1216 | .. code-block:: frr | |
1217 | ||
1218 | router bgp 1 | |
1219 | address-family ipv4 unicast | |
1220 | aggregate-address 10.0.0.0/8 | |
1221 | aggregate-address 20.0.0.0/8 as-set | |
1222 | aggregate-address 40.0.0.0/8 summary-only | |
ac2201bb | 1223 | aggregate-address 50.0.0.0/8 route-map aggr-rmap |
5101fece | 1224 | exit-address-family |
1225 | ||
1226 | ||
1227 | .. _bgp-route-aggregation-ipv6: | |
1228 | ||
1229 | Route Aggregation-IPv6 Address Family | |
1230 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | |
1231 | ||
5101fece | 1232 | .. clicmd:: aggregate-address X:X::X:X/M |
1233 | ||
1234 | This command specifies an aggregate address. | |
1235 | ||
ac2201bb DA |
1236 | .. clicmd:: aggregate-address X:X::X:X/M route-map NAME |
1237 | ||
1238 | Apply a route-map for an aggregated prefix. | |
1239 | ||
a87d2ef7 DA |
1240 | .. clicmd:: aggregate-address X:X::X:X/M origin <egp|igp|incomplete> |
1241 | ||
1242 | Override ORIGIN for an aggregated prefix. | |
1243 | ||
5101fece | 1244 | .. clicmd:: aggregate-address X:X::X:X/M as-set |
1245 | ||
1246 | This command specifies an aggregate address. Resulting routes include | |
1247 | AS set. | |
1248 | ||
5101fece | 1249 | .. clicmd:: aggregate-address X:X::X:X/M summary-only |
1250 | ||
9a339b7f DA |
1251 | This command specifies an aggregate address. |
1252 | ||
1253 | Longer prefixes advertisements of more specific routes to all neighbors are suppressed | |
5101fece | 1254 | |
01338ba1 RZ |
1255 | .. clicmd:: aggregate-address X:X::X:X/M matching-MED-only |
1256 | ||
1257 | Configure the aggregated address to only be created when the routes MED | |
1258 | match, otherwise no aggregated route will be created. | |
1259 | ||
8fbb9c95 RZ |
1260 | .. clicmd:: aggregate-address X:X::X:X/M suppress-map NAME |
1261 | ||
1262 | Similar to `summary-only`, but will only suppress more specific routes that | |
1263 | are matched by the selected route-map. | |
01338ba1 | 1264 | |
5101fece | 1265 | |
03750f1e QY |
1266 | This configuration example sets up an ``aggregate-address`` under the ipv6 |
1267 | address-family. | |
5101fece | 1268 | |
1269 | .. code-block:: frr | |
1270 | ||
1271 | router bgp 1 | |
1272 | address-family ipv6 unicast | |
1273 | aggregate-address 10::0/64 | |
ac2201bb DA |
1274 | aggregate-address 20::0/64 as-set |
1275 | aggregate-address 40::0/64 summary-only | |
1276 | aggregate-address 50::0/64 route-map aggr-rmap | |
5101fece | 1277 | exit-address-family |
c3c5a71f | 1278 | |
03750f1e | 1279 | |
8fcedbd2 | 1280 | .. _bgp-redistribute-to-bgp: |
42fc5d26 | 1281 | |
8fcedbd2 QY |
1282 | Redistribution |
1283 | -------------- | |
42fc5d26 | 1284 | |
a874b986 QY |
1285 | Redistribution configuration should be placed under the ``address-family`` |
1286 | section for the specific AF to redistribute into. Protocol availability for | |
1287 | redistribution is determined by BGP AF; for example, you cannot redistribute | |
1288 | OSPFv3 into ``address-family ipv4 unicast`` as OSPFv3 supports IPv6. | |
1289 | ||
1290 | .. clicmd:: redistribute <babel|connected|eigrp|isis|kernel|openfabric|ospf|ospf6|rip|ripng|sharp|static|table> [metric (0-4294967295)] [route-map WORD] | |
1291 | ||
03750f1e | 1292 | Redistribute routes from other protocols into BGP. |
42fc5d26 | 1293 | |
245d354f DA |
1294 | .. clicmd:: redistribute vnc-direct |
1295 | ||
1296 | Redistribute VNC direct (not via zebra) routes to BGP process. | |
1297 | ||
d70583f7 D |
1298 | .. clicmd:: bgp update-delay MAX-DELAY |
1299 | ||
d70583f7 D |
1300 | .. clicmd:: bgp update-delay MAX-DELAY ESTABLISH-WAIT |
1301 | ||
1302 | This feature is used to enable read-only mode on BGP process restart or when | |
1303 | a BGP process is cleared using 'clear ip bgp \*'. Note that this command is | |
1304 | configured at the global level and applies to all bgp instances/vrfs. It | |
1305 | cannot be used at the same time as the "update-delay" command described below, | |
1306 | which is entered in each bgp instance/vrf desired to delay update installation | |
1307 | and advertisements. The global and per-vrf approaches to defining update-delay | |
1308 | are mutually exclusive. | |
1309 | ||
1310 | When applicable, read-only mode would begin as soon as the first peer reaches | |
1311 | Established status and a timer for max-delay seconds is started. During this | |
1312 | mode BGP doesn't run any best-path or generate any updates to its peers. This | |
1313 | mode continues until: | |
1314 | ||
1315 | 1. All the configured peers, except the shutdown peers, have sent explicit EOR | |
1316 | (End-Of-RIB) or an implicit-EOR. The first keep-alive after BGP has reached | |
1317 | Established is considered an implicit-EOR. | |
1318 | If the establish-wait optional value is given, then BGP will wait for | |
1319 | peers to reach established from the beginning of the update-delay till the | |
1320 | establish-wait period is over, i.e. the minimum set of established peers for | |
1321 | which EOR is expected would be peers established during the establish-wait | |
1322 | window, not necessarily all the configured neighbors. | |
1323 | 2. max-delay period is over. | |
1324 | ||
1325 | On hitting any of the above two conditions, BGP resumes the decision process | |
1326 | and generates updates to its peers. | |
1327 | ||
1328 | Default max-delay is 0, i.e. the feature is off by default. | |
1329 | ||
1330 | ||
c1a54c05 | 1331 | .. clicmd:: update-delay MAX-DELAY |
c3c5a71f | 1332 | |
c1a54c05 | 1333 | .. clicmd:: update-delay MAX-DELAY ESTABLISH-WAIT |
c3c5a71f | 1334 | |
c1a54c05 | 1335 | This feature is used to enable read-only mode on BGP process restart or when |
d70583f7 | 1336 | a BGP process is cleared using 'clear ip bgp \*'. Note that this command is |
f563acec | 1337 | configured under the specific bgp instance/vrf that the feature is enabled for. |
d70583f7 D |
1338 | It cannot be used at the same time as the global "bgp update-delay" described |
1339 | above, which is entered at the global level and applies to all bgp instances. | |
1340 | The global and per-vrf approaches to defining update-delay are mutually | |
1341 | exclusive. | |
1342 | ||
1343 | When applicable, read-only mode would begin as soon as the first peer reaches | |
1344 | Established status and a timer for max-delay seconds is started. During this | |
1345 | mode BGP doesn't run any best-path or generate any updates to its peers. This | |
1346 | mode continues until: | |
42fc5d26 | 1347 | |
c1a54c05 QY |
1348 | 1. All the configured peers, except the shutdown peers, have sent explicit EOR |
1349 | (End-Of-RIB) or an implicit-EOR. The first keep-alive after BGP has reached | |
1350 | Established is considered an implicit-EOR. | |
1351 | If the establish-wait optional value is given, then BGP will wait for | |
d1e7591e | 1352 | peers to reach established from the beginning of the update-delay till the |
c1a54c05 QY |
1353 | establish-wait period is over, i.e. the minimum set of established peers for |
1354 | which EOR is expected would be peers established during the establish-wait | |
1355 | window, not necessarily all the configured neighbors. | |
1356 | 2. max-delay period is over. | |
42fc5d26 | 1357 | |
c1a54c05 QY |
1358 | On hitting any of the above two conditions, BGP resumes the decision process |
1359 | and generates updates to its peers. | |
42fc5d26 | 1360 | |
c1a54c05 | 1361 | Default max-delay is 0, i.e. the feature is off by default. |
c3c5a71f | 1362 | |
c1a54c05 | 1363 | .. clicmd:: table-map ROUTE-MAP-NAME |
42fc5d26 | 1364 | |
c1a54c05 QY |
1365 | This feature is used to apply a route-map on route updates from BGP to |
1366 | Zebra. All the applicable match operations are allowed, such as match on | |
1367 | prefix, next-hop, communities, etc. Set operations for this attach-point are | |
1368 | limited to metric and next-hop only. Any operation of this feature does not | |
1369 | affect BGPs internal RIB. | |
42fc5d26 | 1370 | |
c1a54c05 QY |
1371 | Supported for ipv4 and ipv6 address families. It works on multi-paths as |
1372 | well, however, metric setting is based on the best-path only. | |
42fc5d26 | 1373 | |
8fcedbd2 | 1374 | .. _bgp-peers: |
42fc5d26 | 1375 | |
8fcedbd2 QY |
1376 | Peers |
1377 | ----- | |
42fc5d26 | 1378 | |
8fcedbd2 | 1379 | .. _bgp-defining-peers: |
42fc5d26 | 1380 | |
8fcedbd2 QY |
1381 | Defining Peers |
1382 | ^^^^^^^^^^^^^^ | |
42fc5d26 | 1383 | |
c1a54c05 | 1384 | .. clicmd:: neighbor PEER remote-as ASN |
42fc5d26 | 1385 | |
c1a54c05 | 1386 | Creates a new neighbor whose remote-as is ASN. PEER can be an IPv4 address |
9eb95b3b | 1387 | or an IPv6 address or an interface to use for the connection. |
76bd1499 | 1388 | |
9eb95b3b QY |
1389 | .. code-block:: frr |
1390 | ||
1391 | router bgp 1 | |
1392 | neighbor 10.0.0.1 remote-as 2 | |
76bd1499 | 1393 | |
c1a54c05 | 1394 | In this case my router, in AS-1, is trying to peer with AS-2 at 10.0.0.1. |
76bd1499 | 1395 | |
c1a54c05 | 1396 | This command must be the first command used when configuring a neighbor. If |
9eb95b3b | 1397 | the remote-as is not specified, *bgpd* will complain like this: :: |
76bd1499 | 1398 | |
c1a54c05 | 1399 | can't find neighbor 10.0.0.1 |
c3c5a71f | 1400 | |
5413757f DS |
1401 | .. clicmd:: neighbor PEER remote-as internal |
1402 | ||
1403 | Create a peer as you would when you specify an ASN, except that if the | |
1404 | peers ASN is different than mine as specified under the :clicmd:`router bgp ASN` | |
1405 | command the connection will be denied. | |
1406 | ||
5413757f DS |
1407 | .. clicmd:: neighbor PEER remote-as external |
1408 | ||
1409 | Create a peer as you would when you specify an ASN, except that if the | |
1410 | peers ASN is the same as mine as specified under the :clicmd:`router bgp ASN` | |
1411 | command the connection will be denied. | |
42fc5d26 | 1412 | |
03750f1e | 1413 | .. clicmd:: bgp listen range <A.B.C.D/M|X:X::X:X/M> peer-group PGNAME |
d79e0e08 QY |
1414 | |
1415 | Accept connections from any peers in the specified prefix. Configuration | |
1416 | from the specified peer-group is used to configure these peers. | |
1417 | ||
1418 | .. note:: | |
1419 | ||
1420 | When using BGP listen ranges, if the associated peer group has TCP MD5 | |
1421 | authentication configured, your kernel must support this on prefixes. On | |
1422 | Linux, this support was added in kernel version 4.14. If your kernel does | |
1423 | not support this feature you will get a warning in the log file, and the | |
1424 | listen range will only accept connections from peers without MD5 configured. | |
1425 | ||
1426 | Additionally, we have observed that when using this option at scale (several | |
1427 | hundred peers) the kernel may hit its option memory limit. In this situation | |
1428 | you will see error messages like: | |
1429 | ||
1430 | ``bgpd: sockopt_tcp_signature: setsockopt(23): Cannot allocate memory`` | |
1431 | ||
1432 | In this case you need to increase the value of the sysctl | |
1433 | ``net.core.optmem_max`` to allow the kernel to allocate the necessary option | |
1434 | memory. | |
1435 | ||
5b1b6b8b PG |
1436 | .. clicmd:: bgp listen limit <1-65535> |
1437 | ||
1438 | Define the maximum number of peers accepted for one BGP instance. This | |
1439 | limit is set to 100 by default. Increasing this value will really be | |
1440 | possible if more file descriptors are available in the BGP process. This | |
1441 | value is defined by the underlying system (ulimit value), and can be | |
f563acec | 1442 | overridden by `--limit-fds`. More information is available in chapter |
5b1b6b8b PG |
1443 | (:ref:`common-invocation-options`). |
1444 | ||
03750f1e | 1445 | .. clicmd:: coalesce-time (0-4294967295) |
ced26d3d DS |
1446 | |
1447 | The time in milliseconds that BGP will delay before deciding what peers | |
1448 | can be put into an update-group together in order to generate a single | |
1449 | update for them. The default time is 1000. | |
91052810 | 1450 | |
8fcedbd2 | 1451 | .. _bgp-configuring-peers: |
42fc5d26 | 1452 | |
8fcedbd2 QY |
1453 | Configuring Peers |
1454 | ^^^^^^^^^^^^^^^^^ | |
42fc5d26 | 1455 | |
03750f1e | 1456 | .. clicmd:: neighbor PEER shutdown [message MSG...] [rtt (1-65535) [count (1-255)]] |
c3c5a71f | 1457 | |
c1a54c05 QY |
1458 | Shutdown the peer. We can delete the neighbor's configuration by |
1459 | ``no neighbor PEER remote-as ASN`` but all configuration of the neighbor | |
1460 | will be deleted. When you want to preserve the configuration, but want to | |
1461 | drop the BGP peer, use this syntax. | |
c3c5a71f | 1462 | |
70335e0a RZ |
1463 | Optionally you can specify a shutdown message `MSG`. |
1464 | ||
56c07345 | 1465 | Also, you can specify optionally ``rtt`` in milliseconds to automatically |
91052810 DA |
1466 | shutdown the peer if round-trip-time becomes higher than defined. |
1467 | ||
56c07345 | 1468 | Additional ``count`` parameter is the number of keepalive messages to count |
91052810 DA |
1469 | before shutdown the peer if round-trip-time becomes higher than defined. |
1470 | ||
03750f1e | 1471 | .. clicmd:: neighbor PEER disable-connected-check |
c3c5a71f | 1472 | |
c0868e8b QY |
1473 | Allow peerings between directly connected eBGP peers using loopback |
1474 | addresses. | |
c3c5a71f | 1475 | |
8dbe9214 DA |
1476 | .. clicmd:: neighbor PEER disable-link-bw-encoding-ieee |
1477 | ||
1478 | By default bandwidth in extended communities is carried encoded as IEEE | |
1479 | floating-point format, which is according to the draft. | |
1480 | ||
1481 | Older versions have the implementation where extended community bandwidth | |
1482 | value is carried encoded as uint32. To enable backward compatibility we | |
1483 | need to disable IEEE floating-point encoding option per-peer. | |
1484 | ||
ad7d219d DA |
1485 | .. clicmd:: neighbor PEER extended-optional-parameters |
1486 | ||
1487 | Force Extended Optional Parameters Length format to be used for OPEN messages. | |
1488 | ||
1489 | By default, it's disabled. If the standard optional parameters length is | |
1490 | higher than one-octet (255), then extended format is enabled automatically. | |
1491 | ||
1492 | For testing purposes, extended format can be enabled with this command. | |
1493 | ||
03750f1e | 1494 | .. clicmd:: neighbor PEER ebgp-multihop |
42fc5d26 | 1495 | |
164786a9 QY |
1496 | Specifying ``ebgp-multihop`` allows sessions with eBGP neighbors to |
1497 | establish when they are multiple hops away. When the neighbor is not | |
1498 | directly connected and this knob is not enabled, the session will not | |
1499 | establish. | |
1500 | ||
15e6881e DA |
1501 | If the peer's IP address is not in the RIB and is reachable via the |
1502 | default route, then you have to enable ``ip nht resolve-via-default``. | |
1503 | ||
03750f1e | 1504 | .. clicmd:: neighbor PEER description ... |
42fc5d26 | 1505 | |
c1a54c05 | 1506 | Set description of the peer. |
42fc5d26 | 1507 | |
03750f1e | 1508 | .. clicmd:: neighbor PEER interface IFNAME |
42fc5d26 | 1509 | |
c1a54c05 QY |
1510 | When you connect to a BGP peer over an IPv6 link-local address, you have to |
1511 | specify the IFNAME of the interface used for the connection. To specify | |
1512 | IPv4 session addresses, see the ``neighbor PEER update-source`` command | |
1513 | below. | |
42fc5d26 | 1514 | |
da4d6777 QY |
1515 | .. clicmd:: neighbor PEER interface remote-as <internal|external|ASN> |
1516 | ||
1517 | Configure an unnumbered BGP peer. ``PEER`` should be an interface name. The | |
1518 | session will be established via IPv6 link locals. Use ``internal`` for iBGP | |
1519 | and ``external`` for eBGP sessions, or specify an ASN if you wish. | |
1520 | ||
42d623ac | 1521 | .. clicmd:: neighbor PEER next-hop-self [force] |
42fc5d26 | 1522 | |
c1a54c05 | 1523 | This command specifies an announced route's nexthop as being equivalent to |
42d623ac TA |
1524 | the address of the bgp router if it is learned via eBGP. This will also |
1525 | bypass third-party next-hops in favor of the local bgp address. If the | |
1526 | optional keyword ``force`` is specified the modification is done also for | |
1527 | routes learned via iBGP. | |
42fc5d26 | 1528 | |
8b0d734b | 1529 | .. clicmd:: neighbor PEER attribute-unchanged [{as-path|next-hop|med}] |
1530 | ||
1531 | This command specifies attributes to be left unchanged for advertisements | |
1532 | sent to a peer. Use this to leave the next-hop unchanged in ipv6 | |
1533 | configurations, as the route-map directive to leave the next-hop unchanged | |
1534 | is only available for ipv4. | |
1535 | ||
03750f1e | 1536 | .. clicmd:: neighbor PEER update-source <IFNAME|ADDRESS> |
42fc5d26 | 1537 | |
c1a54c05 QY |
1538 | Specify the IPv4 source address to use for the :abbr:`BGP` session to this |
1539 | neighbour, may be specified as either an IPv4 address directly or as an | |
1540 | interface name (in which case the *zebra* daemon MUST be running in order | |
9eb95b3b QY |
1541 | for *bgpd* to be able to retrieve interface state). |
1542 | ||
1543 | .. code-block:: frr | |
42fc5d26 | 1544 | |
c1a54c05 QY |
1545 | router bgp 64555 |
1546 | neighbor foo update-source 192.168.0.1 | |
1547 | neighbor bar update-source lo0 | |
42fc5d26 | 1548 | |
42fc5d26 | 1549 | |
91342239 | 1550 | .. clicmd:: neighbor PEER default-originate [route-map WORD] |
42fc5d26 | 1551 | |
4da7fda3 QY |
1552 | *bgpd*'s default is to not announce the default route (0.0.0.0/0) even if it |
1553 | is in routing table. When you want to announce default routes to the peer, | |
1554 | use this command. | |
42fc5d26 | 1555 | |
91342239 DA |
1556 | If ``route-map`` keyword is specified, then the default route will be |
1557 | originated only if route-map conditions are met. For example, announce | |
1558 | the default route only if ``10.10.10.10/32`` route exists and set an | |
1559 | arbitrary community for a default route. | |
1560 | ||
1561 | .. code-block:: frr | |
1562 | ||
1563 | router bgp 64555 | |
1564 | address-family ipv4 unicast | |
1565 | neighbor 192.168.255.1 default-originate route-map default | |
1566 | ! | |
1567 | ip prefix-list p1 seq 5 permit 10.10.10.10/32 | |
1568 | ! | |
1569 | route-map default permit 10 | |
1570 | match ip address prefix-list p1 | |
1571 | set community 123:123 | |
1572 | ! | |
1573 | ||
c1a54c05 | 1574 | .. clicmd:: neighbor PEER port PORT |
42fc5d26 | 1575 | |
03750f1e | 1576 | .. clicmd:: neighbor PEER password PASSWORD |
e7c105a7 DS |
1577 | |
1578 | Set a MD5 password to be used with the tcp socket that is being used | |
1579 | to connect to the remote peer. Please note if you are using this | |
1580 | command with a large number of peers on linux you should consider | |
1581 | modifying the `net.core.optmem_max` sysctl to a larger value to | |
1582 | avoid out of memory errors from the linux kernel. | |
1583 | ||
c1a54c05 | 1584 | .. clicmd:: neighbor PEER send-community |
42fc5d26 | 1585 | |
03750f1e | 1586 | .. clicmd:: neighbor PEER weight WEIGHT |
42fc5d26 | 1587 | |
c1a54c05 | 1588 | This command specifies a default `weight` value for the neighbor's routes. |
42fc5d26 | 1589 | |
03750f1e | 1590 | .. clicmd:: neighbor PEER maximum-prefix NUMBER [force] |
42fc5d26 | 1591 | |
886026c8 QY |
1592 | Sets a maximum number of prefixes we can receive from a given peer. If this |
1593 | number is exceeded, the BGP session will be destroyed. | |
1594 | ||
1595 | In practice, it is generally preferable to use a prefix-list to limit what | |
1596 | prefixes are received from the peer instead of using this knob. Tearing down | |
1597 | the BGP session when a limit is exceeded is far more destructive than merely | |
1598 | rejecting undesired prefixes. The prefix-list method is also much more | |
1599 | granular and offers much smarter matching criterion than number of received | |
1600 | prefixes, making it more suited to implementing policy. | |
1601 | ||
56c07345 | 1602 | If ``force`` is set, then ALL prefixes are counted for maximum instead of |
c1bcac1d DA |
1603 | accepted only. This is useful for cases where an inbound filter is applied, |
1604 | but you want maximum-prefix to act on ALL (including filtered) prefixes. This | |
1605 | option requires `soft-reconfiguration inbound` to be enabled for the peer. | |
1606 | ||
03750f1e | 1607 | .. clicmd:: neighbor PEER maximum-prefix-out NUMBER |
edf98aa3 DA |
1608 | |
1609 | Sets a maximum number of prefixes we can send to a given peer. | |
1610 | ||
f5399474 DA |
1611 | Since sent prefix count is managed by update-groups, this option |
1612 | creates a separate update-group for outgoing updates. | |
1613 | ||
03750f1e | 1614 | .. clicmd:: neighbor PEER local-as AS-NUMBER [no-prepend] [replace-as] |
42fc5d26 | 1615 | |
c1a54c05 QY |
1616 | Specify an alternate AS for this BGP process when interacting with the |
1617 | specified peer. With no modifiers, the specified local-as is prepended to | |
1618 | the received AS_PATH when receiving routing updates from the peer, and | |
1619 | prepended to the outgoing AS_PATH (after the process local AS) when | |
1620 | transmitting local routes to the peer. | |
42fc5d26 | 1621 | |
c1a54c05 QY |
1622 | If the no-prepend attribute is specified, then the supplied local-as is not |
1623 | prepended to the received AS_PATH. | |
c3c5a71f | 1624 | |
c1a54c05 QY |
1625 | If the replace-as attribute is specified, then only the supplied local-as is |
1626 | prepended to the AS_PATH when transmitting local-route updates to this peer. | |
c3c5a71f | 1627 | |
c1a54c05 | 1628 | Note that replace-as can only be specified if no-prepend is. |
c3c5a71f | 1629 | |
c1a54c05 | 1630 | This command is only allowed for eBGP peers. |
c3c5a71f | 1631 | |
03750f1e | 1632 | .. clicmd:: neighbor <A.B.C.D|X:X::X:X|WORD> as-override |
252c5590 RZ |
1633 | |
1634 | Override AS number of the originating router with the local AS number. | |
1635 | ||
1636 | Usually this configuration is used in PEs (Provider Edge) to replace | |
1637 | the incoming customer AS number so the connected CE (Customer Edge) | |
1638 | can use the same AS number as the other customer sites. This allows | |
1639 | customers of the provider network to use the same AS number across | |
1640 | their sites. | |
1641 | ||
1642 | This command is only allowed for eBGP peers. | |
1643 | ||
03750f1e | 1644 | .. clicmd:: neighbor <A.B.C.D|X:X::X:X|WORD> allowas-in [<(1-10)|origin>] |
ae1e0f32 RZ |
1645 | |
1646 | Accept incoming routes with AS path containing AS number with the same value | |
1647 | as the current system AS. | |
1648 | ||
1649 | This is used when you want to use the same AS number in your sites, but you | |
1650 | can't connect them directly. This is an alternative to | |
1651 | `neighbor WORD as-override`. | |
1652 | ||
f563acec | 1653 | The parameter `(1-10)` configures the amount of accepted occurrences of the |
ae1e0f32 RZ |
1654 | system AS number in AS path. |
1655 | ||
1656 | The parameter `origin` configures BGP to only accept routes originated with | |
1657 | the same AS number as the system. | |
1658 | ||
1659 | This command is only allowed for eBGP peers. | |
1660 | ||
03750f1e | 1661 | .. clicmd:: neighbor <A.B.C.D|X:X::X:X|WORD> addpath-tx-all-paths |
e03bf6fc RZ |
1662 | |
1663 | Configure BGP to send all known paths to neighbor in order to preserve multi | |
1664 | path capabilities inside a network. | |
1665 | ||
03750f1e | 1666 | .. clicmd:: neighbor <A.B.C.D|X:X::X:X|WORD> addpath-tx-bestpath-per-AS |
e03bf6fc RZ |
1667 | |
1668 | Configure BGP to send best known paths to neighbor in order to preserve multi | |
1669 | path capabilities inside a network. | |
1670 | ||
7cb0494d DA |
1671 | .. clicmd:: neighbor <A.B.C.D|X:X::X:X|WORD> disable-addpath-rx |
1672 | ||
1673 | Do not accept additional paths from this neighbor. | |
1674 | ||
03750f1e | 1675 | .. clicmd:: neighbor PEER ttl-security hops NUMBER |
c3c5a71f | 1676 | |
c1a54c05 QY |
1677 | This command enforces Generalized TTL Security Mechanism (GTSM), as |
1678 | specified in RFC 5082. With this command, only neighbors that are the | |
1679 | specified number of hops away will be allowed to become neighbors. This | |
d1e7591e | 1680 | command is mutually exclusive with *ebgp-multihop*. |
42fc5d26 | 1681 | |
03750f1e | 1682 | .. clicmd:: neighbor PEER capability extended-nexthop |
19f2b5e8 DS |
1683 | |
1684 | Allow bgp to negotiate the extended-nexthop capability with it's peer. | |
1685 | If you are peering over a v6 LL address then this capability is turned | |
1686 | on automatically. If you are peering over a v6 Global Address then | |
1687 | turning on this command will allow BGP to install v4 routes with | |
1688 | v6 nexthops if you do not have v4 configured on interfaces. | |
1689 | ||
46dbf9d0 DA |
1690 | .. clicmd:: neighbor <A.B.C.D|X:X::X:X|WORD> accept-own |
1691 | ||
1692 | Enable handling of self-originated VPN routes containing ``accept-own`` community. | |
1693 | ||
1694 | This feature allows you to handle self-originated VPN routes, which a BGP speaker | |
1695 | receives from a route-reflector. A 'self-originated' route is one that was | |
1696 | originally advertised by the speaker itself. As per :rfc:`4271`, a BGP speaker rejects | |
1697 | advertisements that originated the speaker itself. However, the BGP ACCEPT_OWN | |
1698 | mechanism enables a router to accept the prefixes it has advertised, when reflected | |
1699 | from a route-reflector that modifies certain attributes of the prefix. | |
1700 | ||
1701 | A special community called ``accept-own`` is attached to the prefix by the | |
1702 | route-reflector, which is a signal to the receiving router to bypass the ORIGINATOR_ID | |
1703 | and NEXTHOP/MP_REACH_NLRI check. | |
1704 | ||
1705 | Default: disabled. | |
1706 | ||
4f770cf1 DA |
1707 | .. clicmd:: neighbor <A.B.C.D|X:X::X:X|WORD> graceful-shutdown |
1708 | ||
1709 | Mark all routes from this neighbor as less preferred by setting ``graceful-shutdown`` | |
1710 | community, and local-preference to 0. | |
1711 | ||
03750f1e | 1712 | .. clicmd:: bgp fast-external-failover |
eb938189 | 1713 | |
52fb7e96 | 1714 | This command causes bgp to take down ebgp peers immediately |
eb938189 DS |
1715 | when a link flaps. `bgp fast-external-failover` is the default |
1716 | and will not be displayed as part of a `show run`. The no form | |
1717 | of the command turns off this ability. | |
1718 | ||
03750f1e | 1719 | .. clicmd:: bgp default ipv4-unicast |
bc132029 | 1720 | |
5441ad10 TA |
1721 | This command allows the user to specify that the IPv4 Unicast address |
1722 | family is turned on by default or not. This command defaults to on | |
1723 | and is not displayed. | |
bc132029 DS |
1724 | The `no bgp default ipv4-unicast` form of the command is displayed. |
1725 | ||
5441ad10 TA |
1726 | .. clicmd:: bgp default ipv4-multicast |
1727 | ||
1728 | This command allows the user to specify that the IPv4 Multicast address | |
1729 | family is turned on by default or not. This command defaults to off | |
1730 | and is not displayed. | |
1731 | The `bgp default ipv4-multicast` form of the command is displayed. | |
1732 | ||
1733 | .. clicmd:: bgp default ipv4-vpn | |
1734 | ||
1735 | This command allows the user to specify that the IPv4 MPLS VPN address | |
1736 | family is turned on by default or not. This command defaults to off | |
1737 | and is not displayed. | |
1738 | The `bgp default ipv4-vpn` form of the command is displayed. | |
1739 | ||
1740 | .. clicmd:: bgp default ipv4-flowspec | |
1741 | ||
1742 | This command allows the user to specify that the IPv4 Flowspec address | |
1743 | family is turned on by default or not. This command defaults to off | |
1744 | and is not displayed. | |
1745 | The `bgp default ipv4-flowspec` form of the command is displayed. | |
1746 | ||
2c853e5e DA |
1747 | .. clicmd:: bgp default ipv6-unicast |
1748 | ||
5441ad10 TA |
1749 | This command allows the user to specify that the IPv6 Unicast address |
1750 | family is turned on by default or not. This command defaults to off | |
1751 | and is not displayed. | |
2c853e5e DA |
1752 | The `bgp default ipv6-unicast` form of the command is displayed. |
1753 | ||
5441ad10 TA |
1754 | .. clicmd:: bgp default ipv6-multicast |
1755 | ||
1756 | This command allows the user to specify that the IPv6 Multicast address | |
1757 | family is turned on by default or not. This command defaults to off | |
1758 | and is not displayed. | |
1759 | The `bgp default ipv6-multicast` form of the command is displayed. | |
1760 | ||
1761 | .. clicmd:: bgp default ipv6-vpn | |
1762 | ||
1763 | This command allows the user to specify that the IPv6 MPLS VPN address | |
1764 | family is turned on by default or not. This command defaults to off | |
1765 | and is not displayed. | |
1766 | The `bgp default ipv6-vpn` form of the command is displayed. | |
1767 | ||
1768 | .. clicmd:: bgp default ipv6-flowspec | |
1769 | ||
1770 | This command allows the user to specify that the IPv6 Flowspec address | |
1771 | family is turned on by default or not. This command defaults to off | |
1772 | and is not displayed. | |
1773 | The `bgp default ipv6-flowspec` form of the command is displayed. | |
1774 | ||
1775 | .. clicmd:: bgp default l2vpn-evpn | |
1776 | ||
1777 | This command allows the user to specify that the L2VPN EVPN address | |
1778 | family is turned on by default or not. This command defaults to off | |
1779 | and is not displayed. | |
1780 | The `bgp default l2vpn-evpn` form of the command is displayed. | |
1781 | ||
03750f1e | 1782 | .. clicmd:: bgp default show-hostname |
7d981695 DA |
1783 | |
1784 | This command shows the hostname of the peer in certain BGP commands | |
1785 | outputs. It's easier to troubleshoot if you have a number of BGP peers. | |
1786 | ||
03750f1e | 1787 | .. clicmd:: bgp default show-nexthop-hostname |
7d981695 DA |
1788 | |
1789 | This command shows the hostname of the next-hop in certain BGP commands | |
1790 | outputs. It's easier to troubleshoot if you have a number of BGP peers | |
1791 | and a number of routes to check. | |
1792 | ||
03750f1e | 1793 | .. clicmd:: neighbor PEER advertisement-interval (0-600) |
e10dda57 DS |
1794 | |
1795 | Setup the minimum route advertisement interval(mrai) for the | |
1796 | peer in question. This number is between 0 and 600 seconds, | |
1797 | with the default advertisement interval being 0. | |
1798 | ||
0c969c0f QY |
1799 | .. clicmd:: neighbor PEER timers (0-65535) (0-65535) |
1800 | ||
1801 | Set keepalive and hold timers for a neighbor. The first value is keepalive | |
1802 | and the second is hold time. | |
1803 | ||
d7cd3d09 | 1804 | .. clicmd:: neighbor PEER timers connect (1-65535) |
0c969c0f QY |
1805 | |
1806 | Set connect timer for a neighbor. The connect timer controls how long BGP | |
1807 | waits between connection attempts to a neighbor. | |
1808 | ||
03750f1e | 1809 | .. clicmd:: neighbor PEER timers delayopen (1-240) |
94abf9b4 DS |
1810 | |
1811 | This command allows the user enable the | |
1812 | `RFC 4271 <https://tools.ietf.org/html/rfc4271/>` DelayOpenTimer with the | |
1813 | specified interval or disable it with the negating command for the peer. By | |
1814 | default, the DelayOpenTimer is disabled. The timer interval may be set to a | |
1815 | duration of 1 to 240 seconds. | |
1816 | ||
b042667a TI |
1817 | .. clicmd:: bgp minimum-holdtime (1-65535) |
1818 | ||
1819 | This command allows user to prevent session establishment with BGP peers | |
1820 | with lower holdtime less than configured minimum holdtime. | |
1821 | When this command is not set, minimum holdtime does not work. | |
1822 | ||
d1adb448 PG |
1823 | .. clicmd:: bgp tcp-keepalive (1-65535) (1-65535) (1-30) |
1824 | ||
1825 | This command allows user to configure TCP keepalive with new BGP peers. | |
1826 | Each parameter respectively stands for TCP keepalive idle timer (seconds), | |
1827 | interval (seconds), and maximum probes. By default, TCP keepalive is | |
1828 | disabled. | |
1829 | ||
4e853678 DS |
1830 | Displaying Information about Peers |
1831 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | |
1832 | ||
4e853678 DS |
1833 | .. clicmd:: show bgp <afi> <safi> neighbors WORD bestpath-routes [json] [wide] |
1834 | ||
1835 | For the given neighbor, WORD, that is specified list the routes selected | |
1836 | by BGP as having the best path. | |
1837 | ||
8fcedbd2 | 1838 | .. _bgp-peer-filtering: |
42fc5d26 | 1839 | |
8fcedbd2 QY |
1840 | Peer Filtering |
1841 | ^^^^^^^^^^^^^^ | |
42fc5d26 | 1842 | |
c1a54c05 | 1843 | .. clicmd:: neighbor PEER distribute-list NAME [in|out] |
42fc5d26 | 1844 | |
c1a54c05 QY |
1845 | This command specifies a distribute-list for the peer. `direct` is |
1846 | ``in`` or ``out``. | |
42fc5d26 | 1847 | |
29adcd50 | 1848 | .. clicmd:: neighbor PEER prefix-list NAME [in|out] |
42fc5d26 | 1849 | |
29adcd50 | 1850 | .. clicmd:: neighbor PEER filter-list NAME [in|out] |
42fc5d26 | 1851 | |
c1a54c05 | 1852 | .. clicmd:: neighbor PEER route-map NAME [in|out] |
42fc5d26 | 1853 | |
c1a54c05 | 1854 | Apply a route-map on the neighbor. `direct` must be `in` or `out`. |
42fc5d26 | 1855 | |
29adcd50 | 1856 | .. clicmd:: bgp route-reflector allow-outbound-policy |
42fc5d26 | 1857 | |
c1a54c05 QY |
1858 | By default, attribute modification via route-map policy out is not reflected |
1859 | on reflected routes. This option allows the modifications to be reflected as | |
1860 | well. Once enabled, it affects all reflected routes. | |
42fc5d26 | 1861 | |
03750f1e | 1862 | .. clicmd:: neighbor PEER sender-as-path-loop-detection |
583a9fd4 RZ |
1863 | |
1864 | Enable the detection of sender side AS path loops and filter the | |
1865 | bad routes before they are sent. | |
1866 | ||
1867 | This setting is disabled by default. | |
1868 | ||
0efdf0fe | 1869 | .. _bgp-peer-group: |
42fc5d26 | 1870 | |
8fcedbd2 QY |
1871 | Peer Groups |
1872 | ^^^^^^^^^^^ | |
42fc5d26 | 1873 | |
199ad5c4 LB |
1874 | Peer groups are used to help improve scaling by generating the same |
1875 | update information to all members of a peer group. Note that this means | |
1876 | that the routes generated by a member of a peer group will be sent back | |
1877 | to that originating peer with the originator identifier attribute set to | |
1878 | indicated the originating peer. All peers not associated with a | |
1879 | specific peer group are treated as belonging to a default peer group, | |
1880 | and will share updates. | |
1881 | ||
c1a54c05 | 1882 | .. clicmd:: neighbor WORD peer-group |
42fc5d26 | 1883 | |
c1a54c05 | 1884 | This command defines a new peer group. |
42fc5d26 | 1885 | |
d7b9898c | 1886 | .. clicmd:: neighbor PEER peer-group PGNAME |
c3c5a71f | 1887 | |
c1a54c05 | 1888 | This command bind specific peer to peer group WORD. |
42fc5d26 | 1889 | |
199ad5c4 LB |
1890 | .. clicmd:: neighbor PEER solo |
1891 | ||
1892 | This command is used to indicate that routes advertised by the peer | |
1893 | should not be reflected back to the peer. This command only is only | |
1894 | meaningful when there is a single peer defined in the peer-group. | |
1895 | ||
65c0fc12 DA |
1896 | .. clicmd:: show [ip] bgp peer-group [json] |
1897 | ||
1898 | This command displays configured BGP peer-groups. | |
1899 | ||
1900 | .. code-block:: frr | |
1901 | ||
1902 | exit1-debian-9# show bgp peer-group | |
1903 | ||
1904 | BGP peer-group test1, remote AS 65001 | |
1905 | Peer-group type is external | |
1906 | Configured address-families: IPv4 Unicast; IPv6 Unicast; | |
1907 | 1 IPv4 listen range(s) | |
1908 | 192.168.100.0/24 | |
1909 | 2 IPv6 listen range(s) | |
1910 | 2001:db8:1::/64 | |
1911 | 2001:db8:2::/64 | |
1912 | Peer-group members: | |
1913 | 192.168.200.1 Active | |
1914 | 2001:db8::1 Active | |
1915 | ||
1916 | BGP peer-group test2 | |
1917 | Peer-group type is external | |
1918 | Configured address-families: IPv4 Unicast; | |
1919 | ||
1920 | Optional ``json`` parameter is used to display JSON output. | |
1921 | ||
1922 | .. code-block:: frr | |
1923 | ||
1924 | { | |
1925 | "test1":{ | |
1926 | "remoteAs":65001, | |
1927 | "type":"external", | |
1928 | "addressFamiliesConfigured":[ | |
1929 | "IPv4 Unicast", | |
1930 | "IPv6 Unicast" | |
1931 | ], | |
1932 | "dynamicRanges":{ | |
1933 | "IPv4":{ | |
1934 | "count":1, | |
1935 | "ranges":[ | |
1936 | "192.168.100.0\/24" | |
1937 | ] | |
1938 | }, | |
1939 | "IPv6":{ | |
1940 | "count":2, | |
1941 | "ranges":[ | |
1942 | "2001:db8:1::\/64", | |
1943 | "2001:db8:2::\/64" | |
1944 | ] | |
1945 | } | |
1946 | }, | |
1947 | "members":{ | |
1948 | "192.168.200.1":{ | |
1949 | "status":"Active" | |
1950 | }, | |
1951 | "2001:db8::1":{ | |
1952 | "status":"Active" | |
1953 | } | |
1954 | } | |
1955 | }, | |
1956 | "test2":{ | |
1957 | "type":"external", | |
1958 | "addressFamiliesConfigured":[ | |
1959 | "IPv4 Unicast" | |
1960 | ] | |
1961 | } | |
1962 | } | |
1963 | ||
8fcedbd2 QY |
1964 | Capability Negotiation |
1965 | ^^^^^^^^^^^^^^^^^^^^^^ | |
42fc5d26 | 1966 | |
8fcedbd2 | 1967 | .. clicmd:: neighbor PEER strict-capability-match |
42fc5d26 | 1968 | |
c1a54c05 | 1969 | |
8fcedbd2 QY |
1970 | Strictly compares remote capabilities and local capabilities. If |
1971 | capabilities are different, send Unsupported Capability error then reset | |
1972 | connection. | |
42fc5d26 | 1973 | |
8fcedbd2 QY |
1974 | You may want to disable sending Capability Negotiation OPEN message optional |
1975 | parameter to the peer when remote peer does not implement Capability | |
1976 | Negotiation. Please use *dont-capability-negotiate* command to disable the | |
1977 | feature. | |
42fc5d26 | 1978 | |
03750f1e | 1979 | .. clicmd:: neighbor PEER dont-capability-negotiate |
42fc5d26 | 1980 | |
8fcedbd2 QY |
1981 | Suppress sending Capability Negotiation as OPEN message optional parameter |
1982 | to the peer. This command only affects the peer is configured other than | |
1983 | IPv4 unicast configuration. | |
42fc5d26 | 1984 | |
8fcedbd2 QY |
1985 | When remote peer does not have capability negotiation feature, remote peer |
1986 | will not send any capabilities at all. In that case, bgp configures the peer | |
1987 | with configured capabilities. | |
42fc5d26 | 1988 | |
8fcedbd2 QY |
1989 | You may prefer locally configured capabilities more than the negotiated |
1990 | capabilities even though remote peer sends capabilities. If the peer is | |
1991 | configured by *override-capability*, *bgpd* ignores received capabilities | |
1992 | then override negotiated capabilities with configured values. | |
42fc5d26 | 1993 | |
7cdc9530 DS |
1994 | Additionally the operator should be reminded that this feature fundamentally |
1995 | disables the ability to use widely deployed BGP features. BGP unnumbered, | |
1996 | hostname support, AS4, Addpath, Route Refresh, ORF, Dynamic Capabilities, | |
1997 | and graceful restart. | |
1998 | ||
8fcedbd2 | 1999 | .. clicmd:: neighbor PEER override-capability |
42fc5d26 | 2000 | |
c1a54c05 | 2001 | |
8fcedbd2 QY |
2002 | Override the result of Capability Negotiation with local configuration. |
2003 | Ignore remote peer's capability value. | |
42fc5d26 | 2004 | |
8fcedbd2 | 2005 | .. _bgp-as-path-access-lists: |
42fc5d26 | 2006 | |
8fcedbd2 QY |
2007 | AS Path Access Lists |
2008 | -------------------- | |
42fc5d26 QY |
2009 | |
2010 | AS path access list is user defined AS path. | |
2011 | ||
e6e62ee5 | 2012 | .. clicmd:: bgp as-path access-list WORD [seq (0-4294967295)] permit|deny LINE |
42fc5d26 | 2013 | |
c1a54c05 | 2014 | This command defines a new AS path access list. |
42fc5d26 | 2015 | |
b15e8360 | 2016 | .. clicmd:: show bgp as-path-access-list [json] |
42fc5d26 | 2017 | |
b15e8360 RW |
2018 | Display all BGP AS Path access lists. |
2019 | ||
2020 | If the ``json`` option is specified, output is displayed in JSON format. | |
2021 | ||
2022 | .. clicmd:: show bgp as-path-access-list WORD [json] | |
2023 | ||
2024 | Display the specified BGP AS Path access list. | |
2025 | ||
2026 | If the ``json`` option is specified, output is displayed in JSON format. | |
42fc5d26 | 2027 | |
125cec1a DA |
2028 | .. _bgp-bogon-filter-example: |
2029 | ||
2030 | Bogon ASN filter policy configuration example | |
2031 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | |
2032 | ||
2033 | .. code-block:: frr | |
2034 | ||
2035 | bgp as-path access-list 99 permit _0_ | |
2036 | bgp as-path access-list 99 permit _23456_ | |
2037 | bgp as-path access-list 99 permit _1310[0-6][0-9]_|_13107[0-1]_ | |
e6e62ee5 | 2038 | bgp as-path access-list 99 seq 20 permit ^65 |
125cec1a | 2039 | |
8fcedbd2 | 2040 | .. _bgp-using-as-path-in-route-map: |
42fc5d26 QY |
2041 | |
2042 | Using AS Path in Route Map | |
2043 | -------------------------- | |
2044 | ||
03750f1e | 2045 | .. clicmd:: match as-path WORD |
42fc5d26 | 2046 | |
eb1f303d DS |
2047 | For a given as-path, WORD, match it on the BGP as-path given for the prefix |
2048 | and if it matches do normal route-map actions. The no form of the command | |
2049 | removes this match from the route-map. | |
42fc5d26 | 2050 | |
03750f1e | 2051 | .. clicmd:: set as-path prepend AS-PATH |
42fc5d26 | 2052 | |
eb1f303d DS |
2053 | Prepend the given string of AS numbers to the AS_PATH of the BGP path's NLRI. |
2054 | The no form of this command removes this set operation from the route-map. | |
42fc5d26 | 2055 | |
03750f1e | 2056 | .. clicmd:: set as-path prepend last-as NUM |
c1a54c05 QY |
2057 | |
2058 | Prepend the existing last AS number (the leftmost ASN) to the AS_PATH. | |
eb1f303d | 2059 | The no form of this command removes this set operation from the route-map. |
42fc5d26 | 2060 | |
77e3d821 DA |
2061 | .. clicmd:: set as-path replace <any|ASN> |
2062 | ||
2063 | Replace a specific AS number to local AS number. ``any`` replaces each | |
2064 | AS number in the AS-PATH with the local AS number. | |
2065 | ||
0efdf0fe | 2066 | .. _bgp-communities-attribute: |
42fc5d26 | 2067 | |
8fcedbd2 QY |
2068 | Communities Attribute |
2069 | --------------------- | |
42fc5d26 | 2070 | |
8fcedbd2 | 2071 | The BGP communities attribute is widely used for implementing policy routing. |
c1a54c05 QY |
2072 | Network operators can manipulate BGP communities attribute based on their |
2073 | network policy. BGP communities attribute is defined in :rfc:`1997` and | |
2074 | :rfc:`1998`. It is an optional transitive attribute, therefore local policy can | |
2075 | travel through different autonomous system. | |
2076 | ||
8fcedbd2 QY |
2077 | The communities attribute is a set of communities values. Each community value |
2078 | is 4 octet long. The following format is used to define the community value. | |
c1a54c05 | 2079 | |
8fcedbd2 | 2080 | ``AS:VAL`` |
c1a54c05 QY |
2081 | This format represents 4 octet communities value. ``AS`` is high order 2 |
2082 | octet in digit format. ``VAL`` is low order 2 octet in digit format. This | |
2083 | format is useful to define AS oriented policy value. For example, | |
2084 | ``7675:80`` can be used when AS 7675 wants to pass local policy value 80 to | |
2085 | neighboring peer. | |
2086 | ||
8fcedbd2 QY |
2087 | ``internet`` |
2088 | ``internet`` represents well-known communities value 0. | |
c1a54c05 | 2089 | |
cae770d3 C |
2090 | ``graceful-shutdown`` |
2091 | ``graceful-shutdown`` represents well-known communities value | |
2092 | ``GRACEFUL_SHUTDOWN`` ``0xFFFF0000`` ``65535:0``. :rfc:`8326` implements | |
2093 | the purpose Graceful BGP Session Shutdown to reduce the amount of | |
56f0bea7 | 2094 | lost traffic when taking BGP sessions down for maintenance. The use |
cae770d3 C |
2095 | of the community needs to be supported from your peers side to |
2096 | actually have any effect. | |
2097 | ||
2098 | ``accept-own`` | |
2099 | ``accept-own`` represents well-known communities value ``ACCEPT_OWN`` | |
2100 | ``0xFFFF0001`` ``65535:1``. :rfc:`7611` implements a way to signal | |
2101 | to a router to accept routes with a local nexthop address. This | |
2102 | can be the case when doing policing and having traffic having a | |
2103 | nexthop located in another VRF but still local interface to the | |
2104 | router. It is recommended to read the RFC for full details. | |
2105 | ||
2106 | ``route-filter-translated-v4`` | |
2107 | ``route-filter-translated-v4`` represents well-known communities value | |
2108 | ``ROUTE_FILTER_TRANSLATED_v4`` ``0xFFFF0002`` ``65535:2``. | |
2109 | ||
2110 | ``route-filter-v4`` | |
2111 | ``route-filter-v4`` represents well-known communities value | |
2112 | ``ROUTE_FILTER_v4`` ``0xFFFF0003`` ``65535:3``. | |
2113 | ||
2114 | ``route-filter-translated-v6`` | |
2115 | ``route-filter-translated-v6`` represents well-known communities value | |
2116 | ``ROUTE_FILTER_TRANSLATED_v6`` ``0xFFFF0004`` ``65535:4``. | |
2117 | ||
2118 | ``route-filter-v6`` | |
2119 | ``route-filter-v6`` represents well-known communities value | |
2120 | ``ROUTE_FILTER_v6`` ``0xFFFF0005`` ``65535:5``. | |
2121 | ||
2122 | ``llgr-stale`` | |
2123 | ``llgr-stale`` represents well-known communities value ``LLGR_STALE`` | |
2124 | ``0xFFFF0006`` ``65535:6``. | |
56f0bea7 | 2125 | Assigned and intended only for use with routers supporting the |
cae770d3 | 2126 | Long-lived Graceful Restart Capability as described in |
49606d58 | 2127 | [Draft-IETF-uttaro-idr-bgp-persistence]_. |
56f0bea7 | 2128 | Routers receiving routes with this community may (depending on |
cae770d3 C |
2129 | implementation) choose allow to reject or modify routes on the |
2130 | presence or absence of this community. | |
2131 | ||
2132 | ``no-llgr`` | |
2133 | ``no-llgr`` represents well-known communities value ``NO_LLGR`` | |
2134 | ``0xFFFF0007`` ``65535:7``. | |
56f0bea7 | 2135 | Assigned and intended only for use with routers supporting the |
cae770d3 | 2136 | Long-lived Graceful Restart Capability as described in |
49606d58 | 2137 | [Draft-IETF-uttaro-idr-bgp-persistence]_. |
56f0bea7 | 2138 | Routers receiving routes with this community may (depending on |
cae770d3 C |
2139 | implementation) choose allow to reject or modify routes on the |
2140 | presence or absence of this community. | |
2141 | ||
2142 | ``accept-own-nexthop`` | |
2143 | ``accept-own-nexthop`` represents well-known communities value | |
2144 | ``accept-own-nexthop`` ``0xFFFF0008`` ``65535:8``. | |
49606d58 | 2145 | [Draft-IETF-agrewal-idr-accept-own-nexthop]_ describes |
cae770d3 C |
2146 | how to tag and label VPN routes to be able to send traffic between VRFs |
2147 | via an internal layer 2 domain on the same PE device. Refer to | |
49606d58 | 2148 | [Draft-IETF-agrewal-idr-accept-own-nexthop]_ for full details. |
cae770d3 C |
2149 | |
2150 | ``blackhole`` | |
2151 | ``blackhole`` represents well-known communities value ``BLACKHOLE`` | |
2152 | ``0xFFFF029A`` ``65535:666``. :rfc:`7999` documents sending prefixes to | |
2153 | EBGP peers and upstream for the purpose of blackholing traffic. | |
2154 | Prefixes tagged with the this community should normally not be | |
10ae708b DA |
2155 | re-advertised from neighbors of the originating network. Upon receiving |
2156 | ``BLACKHOLE`` community from a BGP speaker, ``NO_ADVERTISE`` community | |
2157 | is added automatically. | |
cae770d3 | 2158 | |
8fcedbd2 | 2159 | ``no-export`` |
c1a54c05 QY |
2160 | ``no-export`` represents well-known communities value ``NO_EXPORT`` |
2161 | ``0xFFFFFF01``. All routes carry this value must not be advertised to | |
2162 | outside a BGP confederation boundary. If neighboring BGP peer is part of BGP | |
2163 | confederation, the peer is considered as inside a BGP confederation | |
2164 | boundary, so the route will be announced to the peer. | |
2165 | ||
8fcedbd2 | 2166 | ``no-advertise`` |
c1a54c05 QY |
2167 | ``no-advertise`` represents well-known communities value ``NO_ADVERTISE`` |
2168 | ``0xFFFFFF02``. All routes carry this value must not be advertise to other | |
2169 | BGP peers. | |
2170 | ||
8fcedbd2 | 2171 | ``local-AS`` |
c1a54c05 QY |
2172 | ``local-AS`` represents well-known communities value ``NO_EXPORT_SUBCONFED`` |
2173 | ``0xFFFFFF03``. All routes carry this value must not be advertised to | |
2174 | external BGP peers. Even if the neighboring router is part of confederation, | |
2175 | it is considered as external BGP peer, so the route will not be announced to | |
2176 | the peer. | |
2177 | ||
cae770d3 C |
2178 | ``no-peer`` |
2179 | ``no-peer`` represents well-known communities value ``NOPEER`` | |
2180 | ``0xFFFFFF04`` ``65535:65284``. :rfc:`3765` is used to communicate to | |
2181 | another network how the originating network want the prefix propagated. | |
2182 | ||
aa9eafa4 QY |
2183 | When the communities attribute is received duplicate community values in the |
2184 | attribute are ignored and value is sorted in numerical order. | |
42fc5d26 | 2185 | |
49606d58 PG |
2186 | .. [Draft-IETF-uttaro-idr-bgp-persistence] <https://tools.ietf.org/id/draft-uttaro-idr-bgp-persistence-04.txt> |
2187 | .. [Draft-IETF-agrewal-idr-accept-own-nexthop] <https://tools.ietf.org/id/draft-agrewal-idr-accept-own-nexthop-00.txt> | |
2188 | ||
0efdf0fe | 2189 | .. _bgp-community-lists: |
42fc5d26 | 2190 | |
8fcedbd2 QY |
2191 | Community Lists |
2192 | ^^^^^^^^^^^^^^^ | |
aa9eafa4 QY |
2193 | Community lists are user defined lists of community attribute values. These |
2194 | lists can be used for matching or manipulating the communities attribute in | |
2195 | UPDATE messages. | |
42fc5d26 | 2196 | |
aa9eafa4 | 2197 | There are two types of community list: |
c1a54c05 | 2198 | |
aa9eafa4 | 2199 | standard |
56f0bea7 | 2200 | This type accepts an explicit value for the attribute. |
aa9eafa4 QY |
2201 | |
2202 | expanded | |
2203 | This type accepts a regular expression. Because the regex must be | |
2204 | interpreted on each use expanded community lists are slower than standard | |
2205 | lists. | |
42fc5d26 | 2206 | |
a64e0ee5 | 2207 | .. clicmd:: bgp community-list standard NAME permit|deny COMMUNITY |
42fc5d26 | 2208 | |
aa9eafa4 QY |
2209 | This command defines a new standard community list. ``COMMUNITY`` is |
2210 | communities value. The ``COMMUNITY`` is compiled into community structure. | |
2211 | We can define multiple community list under same name. In that case match | |
2212 | will happen user defined order. Once the community list matches to | |
2213 | communities attribute in BGP updates it return permit or deny by the | |
2214 | community list definition. When there is no matched entry, deny will be | |
2215 | returned. When ``COMMUNITY`` is empty it matches to any routes. | |
42fc5d26 | 2216 | |
a64e0ee5 | 2217 | .. clicmd:: bgp community-list expanded NAME permit|deny COMMUNITY |
42fc5d26 | 2218 | |
aa9eafa4 QY |
2219 | This command defines a new expanded community list. ``COMMUNITY`` is a |
2220 | string expression of communities attribute. ``COMMUNITY`` can be a regular | |
2221 | expression (:ref:`bgp-regular-expressions`) to match the communities | |
47f47873 PG |
2222 | attribute in BGP updates. The expanded community is only used to filter, |
2223 | not `set` actions. | |
42fc5d26 | 2224 | |
aa9eafa4 QY |
2225 | .. deprecated:: 5.0 |
2226 | It is recommended to use the more explicit versions of this command. | |
42fc5d26 | 2227 | |
a64e0ee5 | 2228 | .. clicmd:: bgp community-list NAME permit|deny COMMUNITY |
aa9eafa4 QY |
2229 | |
2230 | When the community list type is not specified, the community list type is | |
2231 | automatically detected. If ``COMMUNITY`` can be compiled into communities | |
2232 | attribute, the community list is defined as a standard community list. | |
2233 | Otherwise it is defined as an expanded community list. This feature is left | |
2234 | for backward compatibility. Use of this feature is not recommended. | |
42fc5d26 | 2235 | |
03750f1e QY |
2236 | Note that all community lists share the same namespace, so it's not |
2237 | necessary to specify ``standard`` or ``expanded``; these modifiers are | |
2238 | purely aesthetic. | |
42fc5d26 | 2239 | |
36dc43aa | 2240 | .. clicmd:: show bgp community-list [NAME detail] |
42fc5d26 | 2241 | |
aa9eafa4 QY |
2242 | Displays community list information. When ``NAME`` is specified the |
2243 | specified community list's information is shown. | |
c3c5a71f | 2244 | |
c1a54c05 | 2245 | :: |
76bd1499 | 2246 | |
a64e0ee5 | 2247 | # show bgp community-list |
c1a54c05 QY |
2248 | Named Community standard list CLIST |
2249 | permit 7675:80 7675:100 no-export | |
2250 | deny internet | |
2251 | Named Community expanded list EXPAND | |
2252 | permit : | |
76bd1499 | 2253 | |
36dc43aa | 2254 | # show bgp community-list CLIST detail |
c1a54c05 QY |
2255 | Named Community standard list CLIST |
2256 | permit 7675:80 7675:100 no-export | |
2257 | deny internet | |
42fc5d26 | 2258 | |
42fc5d26 | 2259 | |
8fcedbd2 | 2260 | .. _bgp-numbered-community-lists: |
42fc5d26 | 2261 | |
8fcedbd2 QY |
2262 | Numbered Community Lists |
2263 | ^^^^^^^^^^^^^^^^^^^^^^^^ | |
42fc5d26 QY |
2264 | |
2265 | When number is used for BGP community list name, the number has | |
c3c5a71f QY |
2266 | special meanings. Community list number in the range from 1 and 99 is |
2267 | standard community list. Community list number in the range from 100 | |
0757efc0 | 2268 | to 500 is expanded community list. These community lists are called |
c3c5a71f | 2269 | as numbered community lists. On the other hand normal community lists |
42fc5d26 QY |
2270 | is called as named community lists. |
2271 | ||
a64e0ee5 | 2272 | .. clicmd:: bgp community-list (1-99) permit|deny COMMUNITY |
42fc5d26 | 2273 | |
aa9eafa4 QY |
2274 | This command defines a new community list. The argument to (1-99) defines |
2275 | the list identifier. | |
42fc5d26 | 2276 | |
0757efc0 | 2277 | .. clicmd:: bgp community-list (100-500) permit|deny COMMUNITY |
42fc5d26 | 2278 | |
aa9eafa4 | 2279 | This command defines a new expanded community list. The argument to |
0757efc0 | 2280 | (100-500) defines the list identifier. |
42fc5d26 | 2281 | |
6a89dd1e DA |
2282 | .. _bgp-community-alias: |
2283 | ||
2284 | Community alias | |
2285 | ^^^^^^^^^^^^^^^ | |
2286 | ||
2287 | BGP community aliases are useful to quickly identify what communities are set | |
2288 | for a specific prefix in a human-readable format. Especially handy for a huge | |
2289 | amount of communities. Accurately defined aliases can help you faster spot | |
2290 | things on the wire. | |
2291 | ||
2292 | .. clicmd:: bgp community alias NAME ALIAS | |
2293 | ||
2294 | This command creates an alias name for a community that will be used | |
2295 | later in various CLI outputs in a human-readable format. | |
2296 | ||
2297 | .. code-block:: frr | |
2298 | ||
2299 | ~# vtysh -c 'show run' | grep 'bgp community alias' | |
2300 | bgp community alias 65001:14 community-1 | |
2301 | bgp community alias 65001:123:1 lcommunity-1 | |
2302 | ||
2303 | ~# vtysh -c 'show ip bgp 172.16.16.1/32' | |
2304 | BGP routing table entry for 172.16.16.1/32, version 21 | |
2305 | Paths: (2 available, best #2, table default) | |
2306 | Advertised to non peer-group peers: | |
2307 | 65030 | |
2308 | 192.168.0.2 from 192.168.0.2 (172.16.16.1) | |
2309 | Origin incomplete, metric 0, valid, external, best (Neighbor IP) | |
2310 | Community: 65001:12 65001:13 community-1 65001:65534 | |
2311 | Large Community: lcommunity-1 65001:123:2 | |
2312 | Last update: Fri Apr 16 12:51:27 2021 | |
2313 | ||
9f977b2d DA |
2314 | .. clicmd:: show bgp [afi] [safi] [all] alias WORD [wide|json] |
2315 | ||
2316 | Display prefixes with matching BGP community alias. | |
2317 | ||
8fcedbd2 | 2318 | .. _bgp-using-communities-in-route-map: |
42fc5d26 | 2319 | |
8fcedbd2 QY |
2320 | Using Communities in Route Maps |
2321 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | |
42fc5d26 | 2322 | |
aa9eafa4 QY |
2323 | In :ref:`route-map` we can match on or set the BGP communities attribute. Using |
2324 | this feature network operator can implement their network policy based on BGP | |
2325 | communities attribute. | |
42fc5d26 | 2326 | |
b91bf5bd | 2327 | The following commands can be used in route maps: |
42fc5d26 | 2328 | |
80dd0954 DA |
2329 | .. clicmd:: match alias WORD |
2330 | ||
2331 | This command performs match to BGP updates using community alias WORD. When | |
2332 | the one of BGP communities value match to the one of community alias value in | |
2333 | community alias, it is match. | |
2334 | ||
aa9eafa4 | 2335 | .. clicmd:: match community WORD exact-match [exact-match] |
42fc5d26 | 2336 | |
c1a54c05 QY |
2337 | This command perform match to BGP updates using community list WORD. When |
2338 | the one of BGP communities value match to the one of communities value in | |
d1e7591e | 2339 | community list, it is match. When `exact-match` keyword is specified, match |
c1a54c05 QY |
2340 | happen only when BGP updates have completely same communities value |
2341 | specified in the community list. | |
42fc5d26 | 2342 | |
aa9eafa4 | 2343 | .. clicmd:: set community <none|COMMUNITY> additive |
42fc5d26 | 2344 | |
aa9eafa4 QY |
2345 | This command sets the community value in BGP updates. If the attribute is |
2346 | already configured, the newly provided value replaces the old one unless the | |
2347 | ``additive`` keyword is specified, in which case the new value is appended | |
2348 | to the existing value. | |
42fc5d26 | 2349 | |
aa9eafa4 QY |
2350 | If ``none`` is specified as the community value, the communities attribute |
2351 | is not sent. | |
42fc5d26 | 2352 | |
47f47873 PG |
2353 | It is not possible to set an expanded community list. |
2354 | ||
29adcd50 | 2355 | .. clicmd:: set comm-list WORD delete |
c1a54c05 | 2356 | |
aa9eafa4 QY |
2357 | This command remove communities value from BGP communities attribute. The |
2358 | ``word`` is community list name. When BGP route's communities value matches | |
2359 | to the community list ``word``, the communities value is removed. When all | |
2360 | of communities value is removed eventually, the BGP update's communities | |
2361 | attribute is completely removed. | |
42fc5d26 | 2362 | |
8fcedbd2 | 2363 | .. _bgp-communities-example: |
c1a54c05 | 2364 | |
8fcedbd2 QY |
2365 | Example Configuration |
2366 | ^^^^^^^^^^^^^^^^^^^^^ | |
9eb95b3b | 2367 | |
8fcedbd2 QY |
2368 | The following configuration is exemplary of the most typical usage of BGP |
2369 | communities attribute. In the example, AS 7675 provides an upstream Internet | |
2370 | connection to AS 100. When the following configuration exists in AS 7675, the | |
2371 | network operator of AS 100 can set local preference in AS 7675 network by | |
2372 | setting BGP communities attribute to the updates. | |
9eb95b3b QY |
2373 | |
2374 | .. code-block:: frr | |
c1a54c05 QY |
2375 | |
2376 | router bgp 7675 | |
2377 | neighbor 192.168.0.1 remote-as 100 | |
2378 | address-family ipv4 unicast | |
2379 | neighbor 192.168.0.1 route-map RMAP in | |
2380 | exit-address-family | |
2381 | ! | |
a64e0ee5 | 2382 | bgp community-list 70 permit 7675:70 |
a64e0ee5 | 2383 | bgp community-list 80 permit 7675:80 |
a64e0ee5 | 2384 | bgp community-list 90 permit 7675:90 |
c1a54c05 QY |
2385 | ! |
2386 | route-map RMAP permit 10 | |
2387 | match community 70 | |
2388 | set local-preference 70 | |
2389 | ! | |
2390 | route-map RMAP permit 20 | |
2391 | match community 80 | |
2392 | set local-preference 80 | |
2393 | ! | |
2394 | route-map RMAP permit 30 | |
2395 | match community 90 | |
2396 | set local-preference 90 | |
c3c5a71f | 2397 | |
42fc5d26 | 2398 | |
8fcedbd2 QY |
2399 | The following configuration announces ``10.0.0.0/8`` from AS 100 to AS 7675. |
2400 | The route has communities value ``7675:80`` so when above configuration exists | |
2401 | in AS 7675, the announced routes' local preference value will be set to 80. | |
9eb95b3b QY |
2402 | |
2403 | .. code-block:: frr | |
c1a54c05 QY |
2404 | |
2405 | router bgp 100 | |
2406 | network 10.0.0.0/8 | |
2407 | neighbor 192.168.0.2 remote-as 7675 | |
2408 | address-family ipv4 unicast | |
2409 | neighbor 192.168.0.2 route-map RMAP out | |
2410 | exit-address-family | |
2411 | ! | |
2412 | ip prefix-list PLIST permit 10.0.0.0/8 | |
2413 | ! | |
2414 | route-map RMAP permit 10 | |
2415 | match ip address prefix-list PLIST | |
2416 | set community 7675:80 | |
c3c5a71f | 2417 | |
42fc5d26 | 2418 | |
8fcedbd2 QY |
2419 | The following configuration is an example of BGP route filtering using |
2420 | communities attribute. This configuration only permit BGP routes which has BGP | |
8d80b8e2 DA |
2421 | communities value (``0:80`` and ``0:90``) or ``0:100``. The network operator can |
2422 | set special internal communities value at BGP border router, then limit the | |
2423 | BGP route announcements into the internal network. | |
9eb95b3b QY |
2424 | |
2425 | .. code-block:: frr | |
42fc5d26 | 2426 | |
c1a54c05 QY |
2427 | router bgp 7675 |
2428 | neighbor 192.168.0.1 remote-as 100 | |
2429 | address-family ipv4 unicast | |
2430 | neighbor 192.168.0.1 route-map RMAP in | |
2431 | exit-address-family | |
2432 | ! | |
a64e0ee5 | 2433 | bgp community-list 1 permit 0:80 0:90 |
8d80b8e2 | 2434 | bgp community-list 1 permit 0:100 |
c1a54c05 QY |
2435 | ! |
2436 | route-map RMAP permit in | |
2437 | match community 1 | |
c3c5a71f | 2438 | |
42fc5d26 | 2439 | |
8fcedbd2 QY |
2440 | The following example filters BGP routes which have a community value of |
2441 | ``1:1``. When there is no match community-list returns ``deny``. To avoid | |
2442 | filtering all routes, a ``permit`` line is set at the end of the | |
2443 | community-list. | |
9eb95b3b QY |
2444 | |
2445 | .. code-block:: frr | |
42fc5d26 | 2446 | |
c1a54c05 QY |
2447 | router bgp 7675 |
2448 | neighbor 192.168.0.1 remote-as 100 | |
2449 | address-family ipv4 unicast | |
2450 | neighbor 192.168.0.1 route-map RMAP in | |
2451 | exit-address-family | |
2452 | ! | |
a64e0ee5 DA |
2453 | bgp community-list standard FILTER deny 1:1 |
2454 | bgp community-list standard FILTER permit | |
c1a54c05 QY |
2455 | ! |
2456 | route-map RMAP permit 10 | |
2457 | match community FILTER | |
c3c5a71f | 2458 | |
42fc5d26 | 2459 | |
8fcedbd2 QY |
2460 | The communities value keyword ``internet`` has special meanings in standard |
2461 | community lists. In the below example ``internet`` matches all BGP routes even | |
2462 | if the route does not have communities attribute at all. So community list | |
2463 | ``INTERNET`` is the same as ``FILTER`` in the previous example. | |
9eb95b3b QY |
2464 | |
2465 | .. code-block:: frr | |
42fc5d26 | 2466 | |
a64e0ee5 DA |
2467 | bgp community-list standard INTERNET deny 1:1 |
2468 | bgp community-list standard INTERNET permit internet | |
c3c5a71f | 2469 | |
42fc5d26 | 2470 | |
8fcedbd2 QY |
2471 | The following configuration is an example of communities value deletion. With |
2472 | this configuration the community values ``100:1`` and ``100:2`` are removed | |
2473 | from BGP updates. For communities value deletion, only ``permit`` | |
2474 | community-list is used. ``deny`` community-list is ignored. | |
9eb95b3b QY |
2475 | |
2476 | .. code-block:: frr | |
42fc5d26 | 2477 | |
c1a54c05 QY |
2478 | router bgp 7675 |
2479 | neighbor 192.168.0.1 remote-as 100 | |
2480 | address-family ipv4 unicast | |
2481 | neighbor 192.168.0.1 route-map RMAP in | |
2482 | exit-address-family | |
2483 | ! | |
a64e0ee5 | 2484 | bgp community-list standard DEL permit 100:1 100:2 |
c1a54c05 QY |
2485 | ! |
2486 | route-map RMAP permit 10 | |
2487 | set comm-list DEL delete | |
c3c5a71f | 2488 | |
42fc5d26 | 2489 | |
0efdf0fe | 2490 | .. _bgp-extended-communities-attribute: |
42fc5d26 | 2491 | |
8fcedbd2 QY |
2492 | Extended Communities Attribute |
2493 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | |
42fc5d26 | 2494 | |
c1a54c05 QY |
2495 | BGP extended communities attribute is introduced with MPLS VPN/BGP technology. |
2496 | MPLS VPN/BGP expands capability of network infrastructure to provide VPN | |
2497 | functionality. At the same time it requires a new framework for policy routing. | |
2498 | With BGP Extended Communities Attribute we can use Route Target or Site of | |
2499 | Origin for implementing network policy for MPLS VPN/BGP. | |
42fc5d26 | 2500 | |
c1a54c05 QY |
2501 | BGP Extended Communities Attribute is similar to BGP Communities Attribute. It |
2502 | is an optional transitive attribute. BGP Extended Communities Attribute can | |
2503 | carry multiple Extended Community value. Each Extended Community value is | |
2504 | eight octet length. | |
42fc5d26 | 2505 | |
c1a54c05 QY |
2506 | BGP Extended Communities Attribute provides an extended range compared with BGP |
2507 | Communities Attribute. Adding to that there is a type field in each value to | |
2508 | provides community space structure. | |
42fc5d26 | 2509 | |
c1a54c05 QY |
2510 | There are two format to define Extended Community value. One is AS based format |
2511 | the other is IP address based format. | |
42fc5d26 | 2512 | |
8fcedbd2 QY |
2513 | ``AS:VAL`` |
2514 | This is a format to define AS based Extended Community value. ``AS`` part | |
2515 | is 2 octets Global Administrator subfield in Extended Community value. | |
2516 | ``VAL`` part is 4 octets Local Administrator subfield. ``7675:100`` | |
2517 | represents AS 7675 policy value 100. | |
42fc5d26 | 2518 | |
8fcedbd2 | 2519 | ``IP-Address:VAL`` |
c1a54c05 | 2520 | This is a format to define IP address based Extended Community value. |
8fcedbd2 QY |
2521 | ``IP-Address`` part is 4 octets Global Administrator subfield. ``VAL`` part |
2522 | is 2 octets Local Administrator subfield. | |
42fc5d26 | 2523 | |
0efdf0fe | 2524 | .. _bgp-extended-community-lists: |
42fc5d26 | 2525 | |
8fcedbd2 QY |
2526 | Extended Community Lists |
2527 | ^^^^^^^^^^^^^^^^^^^^^^^^ | |
42fc5d26 | 2528 | |
a64e0ee5 | 2529 | .. clicmd:: bgp extcommunity-list standard NAME permit|deny EXTCOMMUNITY |
42fc5d26 | 2530 | |
4da7fda3 QY |
2531 | This command defines a new standard extcommunity-list. `extcommunity` is |
2532 | extended communities value. The `extcommunity` is compiled into extended | |
2533 | community structure. We can define multiple extcommunity-list under same | |
2534 | name. In that case match will happen user defined order. Once the | |
2535 | extcommunity-list matches to extended communities attribute in BGP updates | |
2536 | it return permit or deny based upon the extcommunity-list definition. When | |
2537 | there is no matched entry, deny will be returned. When `extcommunity` is | |
2538 | empty it matches to any routes. | |
42fc5d26 | 2539 | |
ff8f74b6 DA |
2540 | A special handling for ``internet`` community is applied. It matches |
2541 | any community. | |
2542 | ||
a64e0ee5 | 2543 | .. clicmd:: bgp extcommunity-list expanded NAME permit|deny LINE |
42fc5d26 | 2544 | |
4da7fda3 QY |
2545 | This command defines a new expanded extcommunity-list. `line` is a string |
2546 | expression of extended communities attribute. `line` can be a regular | |
2547 | expression (:ref:`bgp-regular-expressions`) to match an extended communities | |
2548 | attribute in BGP updates. | |
42fc5d26 | 2549 | |
03750f1e QY |
2550 | Note that all extended community lists shares a single name space, so it's |
2551 | not necessary to specify their type when creating or destroying them. | |
42fc5d26 | 2552 | |
03750f1e | 2553 | .. clicmd:: show bgp extcommunity-list [NAME detail] |
c1a54c05 | 2554 | |
4da7fda3 | 2555 | This command displays current extcommunity-list information. When `name` is |
03750f1e | 2556 | specified the community list's information is shown. |
c3c5a71f | 2557 | |
42fc5d26 | 2558 | |
0efdf0fe | 2559 | .. _bgp-extended-communities-in-route-map: |
42fc5d26 QY |
2560 | |
2561 | BGP Extended Communities in Route Map | |
8fcedbd2 | 2562 | """"""""""""""""""""""""""""""""""""" |
42fc5d26 | 2563 | |
29adcd50 | 2564 | .. clicmd:: match extcommunity WORD |
42fc5d26 | 2565 | |
48753f73 DA |
2566 | .. clicmd:: set extcommunity none |
2567 | ||
2568 | This command resets the extended community value in BGP updates. If the attribute is | |
2569 | already configured or received from the peer, the attribute is discarded and set to | |
2570 | none. This is useful if you need to strip incoming extended communities. | |
2571 | ||
29adcd50 | 2572 | .. clicmd:: set extcommunity rt EXTCOMMUNITY |
42fc5d26 | 2573 | |
c1a54c05 | 2574 | This command set Route Target value. |
42fc5d26 | 2575 | |
29adcd50 | 2576 | .. clicmd:: set extcommunity soo EXTCOMMUNITY |
c1a54c05 QY |
2577 | |
2578 | This command set Site of Origin value. | |
42fc5d26 | 2579 | |
ed647ed2 | 2580 | .. clicmd:: set extcommunity bandwidth <(1-25600) | cumulative | num-multipaths> [non-transitive] |
2581 | ||
2582 | This command sets the BGP link-bandwidth extended community for the prefix | |
2583 | (best path) for which it is applied. The link-bandwidth can be specified as | |
2584 | an ``explicit value`` (specified in Mbps), or the router can be told to use | |
2585 | the ``cumulative bandwidth`` of all multipaths for the prefix or to compute | |
2586 | it based on the ``number of multipaths``. The link bandwidth extended | |
2587 | community is encoded as ``transitive`` unless the set command explicitly | |
2588 | configures it as ``non-transitive``. | |
2589 | ||
2590 | .. seealso:: :ref:`wecmp_linkbw` | |
47f47873 PG |
2591 | |
2592 | Note that the extended expanded community is only used for `match` rule, not for | |
2593 | `set` actions. | |
2594 | ||
0efdf0fe | 2595 | .. _bgp-large-communities-attribute: |
42fc5d26 | 2596 | |
8fcedbd2 QY |
2597 | Large Communities Attribute |
2598 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^ | |
42fc5d26 QY |
2599 | |
2600 | The BGP Large Communities attribute was introduced in Feb 2017 with | |
c1a54c05 | 2601 | :rfc:`8092`. |
42fc5d26 | 2602 | |
8fcedbd2 QY |
2603 | The BGP Large Communities Attribute is similar to the BGP Communities Attribute |
2604 | except that it has 3 components instead of two and each of which are 4 octets | |
2605 | in length. Large Communities bring additional functionality and convenience | |
2606 | over traditional communities, specifically the fact that the ``GLOBAL`` part | |
2607 | below is now 4 octets wide allowing seamless use in networks using 4-byte ASNs. | |
2608 | ||
2609 | ``GLOBAL:LOCAL1:LOCAL2`` | |
2610 | This is the format to define Large Community values. Referencing :rfc:`8195` | |
2611 | the values are commonly referred to as follows: | |
2612 | ||
2613 | - The ``GLOBAL`` part is a 4 octet Global Administrator field, commonly used | |
2614 | as the operators AS number. | |
2615 | - The ``LOCAL1`` part is a 4 octet Local Data Part 1 subfield referred to as | |
2616 | a function. | |
2617 | - The ``LOCAL2`` part is a 4 octet Local Data Part 2 field and referred to | |
2618 | as the parameter subfield. | |
2619 | ||
2620 | As an example, ``65551:1:10`` represents AS 65551 function 1 and parameter | |
2621 | 10. The referenced RFC above gives some guidelines on recommended usage. | |
42fc5d26 | 2622 | |
0efdf0fe | 2623 | .. _bgp-large-community-lists: |
42fc5d26 | 2624 | |
8fcedbd2 QY |
2625 | Large Community Lists |
2626 | """"""""""""""""""""" | |
42fc5d26 QY |
2627 | |
2628 | Two types of large community lists are supported, namely `standard` and | |
2629 | `expanded`. | |
2630 | ||
a64e0ee5 | 2631 | .. clicmd:: bgp large-community-list standard NAME permit|deny LARGE-COMMUNITY |
42fc5d26 | 2632 | |
4da7fda3 QY |
2633 | This command defines a new standard large-community-list. `large-community` |
2634 | is the Large Community value. We can add multiple large communities under | |
2635 | same name. In that case the match will happen in the user defined order. | |
2636 | Once the large-community-list matches the Large Communities attribute in BGP | |
2637 | updates it will return permit or deny based upon the large-community-list | |
2638 | definition. When there is no matched entry, a deny will be returned. When | |
2639 | `large-community` is empty it matches any routes. | |
42fc5d26 | 2640 | |
a64e0ee5 | 2641 | .. clicmd:: bgp large-community-list expanded NAME permit|deny LINE |
42fc5d26 | 2642 | |
4da7fda3 QY |
2643 | This command defines a new expanded large-community-list. Where `line` is a |
2644 | string matching expression, it will be compared to the entire Large | |
2645 | Communities attribute as a string, with each large-community in order from | |
2646 | lowest to highest. `line` can also be a regular expression which matches | |
2647 | this Large Community attribute. | |
42fc5d26 | 2648 | |
03750f1e QY |
2649 | Note that all community lists share the same namespace, so it's not |
2650 | necessary to specify ``standard`` or ``expanded``; these modifiers are | |
2651 | purely aesthetic. | |
42fc5d26 | 2652 | |
a64e0ee5 | 2653 | .. clicmd:: show bgp large-community-list |
42fc5d26 | 2654 | |
36dc43aa | 2655 | .. clicmd:: show bgp large-community-list NAME detail |
42fc5d26 | 2656 | |
c1a54c05 QY |
2657 | This command display current large-community-list information. When |
2658 | `name` is specified the community list information is shown. | |
42fc5d26 | 2659 | |
29adcd50 | 2660 | .. clicmd:: show ip bgp large-community-info |
c1a54c05 QY |
2661 | |
2662 | This command displays the current large communities in use. | |
42fc5d26 | 2663 | |
0efdf0fe | 2664 | .. _bgp-large-communities-in-route-map: |
42fc5d26 | 2665 | |
8fcedbd2 QY |
2666 | Large Communities in Route Map |
2667 | """""""""""""""""""""""""""""" | |
42fc5d26 | 2668 | |
03ff9a14 | 2669 | .. clicmd:: match large-community LINE [exact-match] |
42fc5d26 | 2670 | |
4da7fda3 QY |
2671 | Where `line` can be a simple string to match, or a regular expression. It |
2672 | is very important to note that this match occurs on the entire | |
c1a54c05 | 2673 | large-community string as a whole, where each large-community is ordered |
03ff9a14 | 2674 | from lowest to highest. When `exact-match` keyword is specified, match |
2675 | happen only when BGP updates have completely same large communities value | |
2676 | specified in the large community list. | |
42fc5d26 | 2677 | |
29adcd50 | 2678 | .. clicmd:: set large-community LARGE-COMMUNITY |
42fc5d26 | 2679 | |
29adcd50 | 2680 | .. clicmd:: set large-community LARGE-COMMUNITY LARGE-COMMUNITY |
42fc5d26 | 2681 | |
29adcd50 | 2682 | .. clicmd:: set large-community LARGE-COMMUNITY additive |
c1a54c05 QY |
2683 | |
2684 | These commands are used for setting large-community values. The first | |
2685 | command will overwrite any large-communities currently present. | |
2686 | The second specifies two large-communities, which overwrites the current | |
2687 | large-community list. The third will add a large-community value without | |
2688 | overwriting other values. Multiple large-community values can be specified. | |
42fc5d26 | 2689 | |
47f47873 PG |
2690 | Note that the large expanded community is only used for `match` rule, not for |
2691 | `set` actions. | |
b572f826 | 2692 | |
d864dd9e EB |
2693 | .. _bgp-roles-and-only-to-customers: |
2694 | ||
2695 | BGP Roles and Only to Customers | |
2696 | ------------------------------- | |
2697 | ||
2698 | BGP roles are defined in :rfc:`9234` and provide an easy way to route leaks | |
2699 | prevention, detection and mitigation. | |
2700 | ||
2701 | To enable its mechanics, you must set your local role to reflect your type of | |
2702 | peering relationship with your neighbor. Possible values of ``LOCAL-ROLE`` are: | |
8f2d6021 EB |
2703 | |
2704 | - provider | |
2705 | - rs-server | |
2706 | - rs-client | |
2707 | - customer | |
2708 | - peer | |
d864dd9e EB |
2709 | |
2710 | The local Role value is negotiated with the new BGP Role capability with a | |
2711 | built-in check of the corresponding value. In case of mismatch the new OPEN | |
2712 | Roles Mismatch Notification <2, 11> would be sent. | |
2713 | ||
2714 | The correct Role pairs are: | |
2715 | ||
2716 | * Provider - Customer | |
2717 | * Peer - Peer | |
2718 | * RS-Server - RS-Client | |
2719 | ||
2720 | .. code-block:: shell | |
2721 | ||
2722 | ~# vtysh -c 'show bgp neighbor' | grep 'Role' | |
2723 | Local Role: customer | |
2724 | Neighbor Role: provider | |
2725 | Role: advertised and received | |
2726 | ||
2727 | If strict-mode is set BGP session won't become established until BGP neighbor | |
8f2d6021 | 2728 | set local Role on its side. This configuration parameter is defined in |
d864dd9e | 2729 | :rfc:`9234` and used to enforce corresponding configuration at your |
8f2d6021 | 2730 | counter-part side. Default value - disabled. |
d864dd9e EB |
2731 | |
2732 | Routes that sent from provider, rs-server, or peer local-role (or if received | |
2733 | by customer, rs-clinet, or peer local-role) will be marked with a new | |
2734 | Only to Customer (OTC) attribute. | |
2735 | ||
2736 | Routes with this attribute can only be sent to your neighbor if your | |
2737 | local-role is provider or rs-server. Routes with this attribute can be | |
2738 | received only if your local-role is customer or rs-client. | |
2739 | ||
8f2d6021 | 2740 | In case of peer-peer relationship routes can be received only if |
d864dd9e EB |
2741 | OTC value is equal to your neighbor AS number. |
2742 | ||
2743 | All these rules with OTC help to detect and mitigate route leaks and | |
2744 | happened automatically if local-role is set. | |
2745 | ||
2746 | .. clicmd:: neighbor PEER local-role LOCAL-ROLE [strict-mode] | |
2747 | ||
2748 | This command set your local-role to ``LOCAL-ROLE``: | |
2749 | <provider|rs-server|rs-client|customer|peer>. | |
2750 | ||
8f2d6021 | 2751 | This role helps to detect and prevent route leaks. |
d864dd9e EB |
2752 | |
2753 | If ``strict-mode`` is set, your neighbor must send you Capability with the | |
2754 | value of his role (by setting local-role on his side). Otherwise, a Role | |
2755 | Mismatch Notification will be sent. | |
2756 | ||
c8a5e5e1 | 2757 | .. _bgp-l3vpn-vrfs: |
b572f826 | 2758 | |
c8a5e5e1 QY |
2759 | L3VPN VRFs |
2760 | ---------- | |
b572f826 | 2761 | |
c8a5e5e1 QY |
2762 | *bgpd* supports :abbr:`L3VPN (Layer 3 Virtual Private Networks)` :abbr:`VRFs |
2763 | (Virtual Routing and Forwarding)` for IPv4 :rfc:`4364` and IPv6 :rfc:`4659`. | |
2764 | L3VPN routes, and their associated VRF MPLS labels, can be distributed to VPN | |
2765 | SAFI neighbors in the *default*, i.e., non VRF, BGP instance. VRF MPLS labels | |
2766 | are reached using *core* MPLS labels which are distributed using LDP or BGP | |
2767 | labeled unicast. *bgpd* also supports inter-VRF route leaking. | |
b572f826 | 2768 | |
b572f826 | 2769 | |
1bb550b6 PG |
2770 | L3VPN over GRE interfaces |
2771 | ^^^^^^^^^^^^^^^^^^^^^^^^^ | |
2772 | ||
2773 | In MPLS-VPN or SRv6-VPN, an L3VPN next-hop entry requires that the path | |
2774 | chosen respectively contains a labelled path or a valid SID IPv6 address. | |
2775 | Otherwise the L3VPN entry will not be installed. It is possible to ignore | |
2776 | that check when the path chosen by the next-hop uses a GRE interface, and | |
2777 | there is a route-map configured at inbound side of ipv4-vpn or ipv6-vpn | |
2778 | address family with following syntax: | |
2779 | ||
2780 | .. clicmd:: set l3vpn next-hop encapsulation gre | |
2781 | ||
2782 | The incoming BGP L3VPN entry is accepted, provided that the next hop of the | |
2783 | L3VPN entry uses a path that takes the GRE tunnel as outgoing interface. The | |
2784 | remote endpoint should be configured just behind the GRE tunnel; remote | |
2785 | device configuration may vary depending whether it acts at edge endpoint or | |
2786 | not: in any case, the expectation is that incoming MPLS traffic received at | |
2787 | this endpoint should be considered as a valid path for L3VPN. | |
2788 | ||
c8a5e5e1 | 2789 | .. _bgp-vrf-route-leaking: |
8fcedbd2 QY |
2790 | |
2791 | VRF Route Leaking | |
c8a5e5e1 | 2792 | ----------------- |
8fcedbd2 QY |
2793 | |
2794 | BGP routes may be leaked (i.e. copied) between a unicast VRF RIB and the VPN | |
f90115c5 LB |
2795 | SAFI RIB of the default VRF for use in MPLS-based L3VPNs. Unicast routes may |
2796 | also be leaked between any VRFs (including the unicast RIB of the default BGP | |
2797 | instanced). A shortcut syntax is also available for specifying leaking from one | |
f563acec | 2798 | VRF to another VRF using the default instance's VPN RIB as the intermediary. A |
f90115c5 | 2799 | common application of the VRF-VRF feature is to connect a customer's private |
8fcedbd2 QY |
2800 | routing domain to a provider's VPN service. Leaking is configured from the |
2801 | point of view of an individual VRF: ``import`` refers to routes leaked from VPN | |
2802 | to a unicast VRF, whereas ``export`` refers to routes leaked from a unicast VRF | |
2803 | to VPN. | |
2804 | ||
2805 | Required parameters | |
c8a5e5e1 | 2806 | ^^^^^^^^^^^^^^^^^^^ |
b572f826 | 2807 | |
4da7fda3 QY |
2808 | Routes exported from a unicast VRF to the VPN RIB must be augmented by two |
2809 | parameters: | |
2810 | ||
2811 | - an :abbr:`RD (Route Distinguisher)` | |
2812 | - an :abbr:`RTLIST (Route-target List)` | |
2813 | ||
2814 | Configuration for these exported routes must, at a minimum, specify these two | |
2815 | parameters. | |
2816 | ||
2817 | Routes imported from the VPN RIB to a unicast VRF are selected according to | |
2818 | their RTLISTs. Routes whose RTLIST contains at least one route-target in | |
2819 | common with the configured import RTLIST are leaked. Configuration for these | |
2820 | imported routes must specify an RTLIST to be matched. | |
2821 | ||
2822 | The RD, which carries no semantic value, is intended to make the route unique | |
2823 | in the VPN RIB among all routes of its prefix that originate from all the | |
2824 | customers and sites that are attached to the provider's VPN service. | |
2825 | Accordingly, each site of each customer is typically assigned an RD that is | |
2826 | unique across the entire provider network. | |
2827 | ||
2828 | The RTLIST is a set of route-target extended community values whose purpose is | |
2829 | to specify route-leaking policy. Typically, a customer is assigned a single | |
2830 | route-target value for import and export to be used at all customer sites. This | |
2831 | configuration specifies a simple topology wherein a customer has a single | |
2832 | routing domain which is shared across all its sites. More complex routing | |
2833 | topologies are possible through use of additional route-targets to augment the | |
2834 | leaking of sets of routes in various ways. | |
b572f826 | 2835 | |
e967a1d0 DS |
2836 | When using the shortcut syntax for vrf-to-vrf leaking, the RD and RT are |
2837 | auto-derived. | |
fb3d9f3e | 2838 | |
8fcedbd2 | 2839 | General configuration |
c8a5e5e1 | 2840 | ^^^^^^^^^^^^^^^^^^^^^ |
b572f826 | 2841 | |
f90115c5 | 2842 | Configuration of route leaking between a unicast VRF RIB and the VPN SAFI RIB |
4da7fda3 QY |
2843 | of the default VRF is accomplished via commands in the context of a VRF |
2844 | address-family: | |
b572f826 | 2845 | |
b572f826 PZ |
2846 | .. clicmd:: rd vpn export AS:NN|IP:nn |
2847 | ||
4da7fda3 QY |
2848 | Specifies the route distinguisher to be added to a route exported from the |
2849 | current unicast VRF to VPN. | |
b572f826 | 2850 | |
b572f826 PZ |
2851 | .. clicmd:: rt vpn import|export|both RTLIST... |
2852 | ||
4da7fda3 QY |
2853 | Specifies the route-target list to be attached to a route (export) or the |
2854 | route-target list to match against (import) when exporting/importing between | |
2855 | the current unicast VRF and VPN. | |
b572f826 | 2856 | |
4da7fda3 QY |
2857 | The RTLIST is a space-separated list of route-targets, which are BGP |
2858 | extended community values as described in | |
b572f826 PZ |
2859 | :ref:`bgp-extended-communities-attribute`. |
2860 | ||
e70e9f8e | 2861 | .. clicmd:: label vpn export (0..1048575)|auto |
b572f826 | 2862 | |
8a2124f7 | 2863 | Enables an MPLS label to be attached to a route exported from the current |
2864 | unicast VRF to VPN. If the value specified is ``auto``, the label value is | |
2865 | automatically assigned from a pool maintained by the Zebra daemon. If Zebra | |
2866 | is not running, or if this command is not configured, automatic label | |
2867 | assignment will not complete, which will block corresponding route export. | |
b572f826 | 2868 | |
b572f826 PZ |
2869 | .. clicmd:: nexthop vpn export A.B.C.D|X:X::X:X |
2870 | ||
4da7fda3 QY |
2871 | Specifies an optional nexthop value to be assigned to a route exported from |
2872 | the current unicast VRF to VPN. If left unspecified, the nexthop will be set | |
2873 | to 0.0.0.0 or 0:0::0:0 (self). | |
b572f826 | 2874 | |
b572f826 PZ |
2875 | .. clicmd:: route-map vpn import|export MAP |
2876 | ||
4da7fda3 | 2877 | Specifies an optional route-map to be applied to routes imported or exported |
d1e7591e | 2878 | between the current unicast VRF and VPN. |
b572f826 | 2879 | |
b572f826 PZ |
2880 | .. clicmd:: import|export vpn |
2881 | ||
d1e7591e | 2882 | Enables import or export of routes between the current unicast VRF and VPN. |
b572f826 | 2883 | |
fb3d9f3e DS |
2884 | .. clicmd:: import vrf VRFNAME |
2885 | ||
e967a1d0 DS |
2886 | Shortcut syntax for specifying automatic leaking from vrf VRFNAME to |
2887 | the current VRF using the VPN RIB as intermediary. The RD and RT | |
2888 | are auto derived and should not be specified explicitly for either the | |
2889 | source or destination VRF's. | |
2890 | ||
2891 | This shortcut syntax mode is not compatible with the explicit | |
2892 | `import vpn` and `export vpn` statements for the two VRF's involved. | |
2893 | The CLI will disallow attempts to configure incompatible leaking | |
2894 | modes. | |
fb3d9f3e | 2895 | |
a486300b PG |
2896 | .. clicmd:: bgp retain route-target all |
2897 | ||
2898 | It is possible to retain or not VPN prefixes that are not imported by local | |
2899 | VRF configuration. This can be done via the following command in the context | |
2900 | of the global VPNv4/VPNv6 family. This command defaults to on and is not | |
2901 | displayed. | |
2902 | The `no bgp retain route-target all` form of the command is displayed. | |
2903 | ||
01da2d26 DA |
2904 | .. clicmd:: neighbor <A.B.C.D|X:X::X:X|WORD> soo EXTCOMMUNITY |
2905 | ||
2906 | Without this command, SoO extended community attribute is configured using | |
2907 | an inbound route map that sets the SoO value during the update process. | |
2908 | With the introduction of the new BGP per-neighbor Site-of-Origin (SoO) feature, | |
2909 | two new commands configured in sub-modes under router configuration mode | |
2910 | simplify the SoO value configuration. | |
2911 | ||
2912 | If we configure SoO per neighbor at PEs, the SoO community is automatically | |
2913 | added for all routes from the CPEs. Routes are validated and prevented from | |
2914 | being sent back to the same CPE (e.g.: multi-site). This is especially needed | |
2915 | when using ``as-override`` or ``allowas-in`` to prevent routing loops. | |
2916 | ||
4cd690ae PG |
2917 | .. clicmd:: mpls bgp forwarding |
2918 | ||
2919 | It is possible to permit BGP install VPN prefixes without transport labels, | |
2920 | by issuing the following command under the interface configuration context. | |
2921 | This configuration will install VPN prefixes originated from an e-bgp session, | |
2922 | and with the next-hop directly connected. | |
2923 | ||
4ccd4033 HS |
2924 | .. _bgp-l3vpn-srv6: |
2925 | ||
2926 | L3VPN SRv6 | |
2927 | ---------- | |
2928 | ||
2929 | .. clicmd:: segment-routing srv6 | |
2930 | ||
2931 | Use SRv6 backend with BGP L3VPN, and go to its configuration node. | |
2932 | ||
2933 | .. clicmd:: locator NAME | |
2934 | ||
2935 | Specify the SRv6 locator to be used for SRv6 L3VPN. The Locator name must | |
2936 | be set in zebra, but user can set it in any order. | |
42fc5d26 | 2937 | |
2d8c098a CS |
2938 | General configuration |
2939 | ^^^^^^^^^^^^^^^^^^^^^ | |
2940 | ||
2941 | Configuration of the SRv6 SID used to advertise a L3VPN for both IPv4 and IPv6 | |
2942 | is accomplished via the following command in the context of a VRF: | |
2943 | ||
8265cbc7 | 2944 | .. clicmd:: sid vpn per-vrf export (1..1048575)|auto |
2d8c098a CS |
2945 | |
2946 | Enables a SRv6 SID to be attached to a route exported from the current | |
2947 | unicast VRF to VPN. A single SID is used for both IPv4 and IPv6 address | |
2948 | families. If you want to set a SID for only IPv4 address family or IPv6 | |
8265cbc7 | 2949 | address family, you need to use the command ``sid vpn export (1..1048575)|auto`` |
2d8c098a CS |
2950 | in the context of an address-family. If the value specified is ``auto``, |
2951 | the SID value is automatically assigned from a pool maintained by the Zebra | |
2952 | daemon. If Zebra is not running, or if this command is not configured, automatic | |
2953 | SID assignment will not complete, which will block corresponding route export. | |
2954 | ||
b6c34e85 CS |
2955 | .. _bgp-evpn: |
2956 | ||
2957 | Ethernet Virtual Network - EVPN | |
2958 | ------------------------------- | |
2959 | ||
0a4e0034 JAG |
2960 | Note: When using EVPN features and if you have a large number of hosts, make |
2961 | sure to adjust the size of the arp neighbor cache to avoid neighbor table | |
2962 | overflow and/or excessive garbage collection. On Linux, the size of the table | |
2963 | and garbage collection frequency can be controlled via the following | |
2964 | sysctl configurations: | |
2965 | ||
2966 | .. code-block:: shell | |
2967 | ||
2968 | net.ipv4.neigh.default.gc_thresh1 | |
2969 | net.ipv4.neigh.default.gc_thresh2 | |
2970 | net.ipv4.neigh.default.gc_thresh3 | |
2971 | ||
2972 | net.ipv6.neigh.default.gc_thresh1 | |
2973 | net.ipv6.neigh.default.gc_thresh2 | |
2974 | net.ipv6.neigh.default.gc_thresh3 | |
2975 | ||
2976 | For more information, see ``man 7 arp``. | |
2977 | ||
433d9566 TA |
2978 | .. _bgp-enabling-evpn: |
2979 | ||
2980 | Enabling EVPN | |
2981 | ^^^^^^^^^^^^^ | |
2982 | ||
2983 | EVPN should be enabled on the BGP instance corresponding to the VRF acting as | |
2984 | the underlay for the VXLAN tunneling. In most circumstances this will be the | |
2985 | default VRF. The command to enable EVPN for a BGP instance is | |
2986 | ``advertise-all-vni`` which lives under ``address-family l2vpn evpn``: | |
2987 | ||
2988 | .. code-block:: frr | |
2989 | ||
2990 | router bgp 65001 | |
2991 | ! | |
2992 | address-family l2vpn evpn | |
2993 | advertise-all-vni | |
2994 | ||
2995 | A more comprehensive configuration example can be found in the :ref:`evpn` page. | |
2996 | ||
0f33e6df SW |
2997 | .. _bgp-evpn-l3-route-targets: |
2998 | ||
2999 | EVPN L3 Route-Targets | |
3000 | ^^^^^^^^^^^^^^^^^^^^^ | |
3001 | ||
3002 | .. clicmd:: route-target <import|export|both> <RTLIST|auto> | |
3003 | ||
133c000c | 3004 | Modify the route-target set for EVPN advertised type-2/type-5 routes. |
0f33e6df SW |
3005 | RTLIST is a list of any of matching |
3006 | ``(A.B.C.D:MN|EF:OPQR|GHJK:MN|*:OPQR|*:MN)`` where ``*`` indicates wildcard | |
3007 | matching for the AS number. It will be set to match any AS number. This is | |
3008 | useful in datacenter deployments with Downstream VNI. ``auto`` is used to | |
3009 | retain the autoconfigure that is default behavior for L3 RTs. | |
3010 | ||
b6c34e85 CS |
3011 | .. _bgp-evpn-advertise-pip: |
3012 | ||
3013 | EVPN advertise-PIP | |
3014 | ^^^^^^^^^^^^^^^^^^ | |
3015 | ||
3016 | In a EVPN symmetric routing MLAG deployment, all EVPN routes advertised | |
3017 | with anycast-IP as next-hop IP and anycast MAC as the Router MAC (RMAC - in | |
3018 | BGP EVPN Extended-Community). | |
3019 | EVPN picks up the next-hop IP from the VxLAN interface's local tunnel IP and | |
3020 | the RMAC is obtained from the MAC of the L3VNI's SVI interface. | |
3021 | Note: Next-hop IP is used for EVPN routes whether symmetric routing is | |
3022 | deployed or not but the RMAC is only relevant for symmetric routing scenario. | |
3023 | ||
3024 | Current behavior is not ideal for Prefix (type-5) and self (type-2) | |
3025 | routes. This is because the traffic from remote VTEPs routed sub optimally | |
3026 | if they land on the system where the route does not belong. | |
3027 | ||
3028 | The advertise-pip feature advertises Prefix (type-5) and self (type-2) | |
3029 | routes with system's individual (primary) IP as the next-hop and individual | |
3030 | (system) MAC as Router-MAC (RMAC), while leaving the behavior unchanged for | |
3031 | other EVPN routes. | |
3032 | ||
3033 | To support this feature there needs to have ability to co-exist a | |
3034 | (system-MAC, system-IP) pair with a (anycast-MAC, anycast-IP) pair with the | |
3035 | ability to terminate VxLAN-encapsulated packets received for either pair on | |
0a4e0034 | 3036 | the same L3VNI (i.e associated VLAN). This capability is needed per tenant |
b6c34e85 CS |
3037 | VRF instance. |
3038 | ||
0a4e0034 | 3039 | To derive the system-MAC and the anycast MAC, there must be a |
b6c34e85 CS |
3040 | separate/additional MAC-VLAN interface corresponding to L3VNI’s SVI. |
3041 | The SVI interface’s MAC address can be interpreted as system-MAC | |
3042 | and MAC-VLAN interface's MAC as anycast MAC. | |
3043 | ||
3044 | To derive system-IP and anycast-IP, the default BGP instance's router-id is used | |
3045 | as system-IP and the VxLAN interface’s local tunnel IP as the anycast-IP. | |
3046 | ||
3047 | User has an option to configure the system-IP and/or system-MAC value if the | |
3048 | auto derived value is not preferred. | |
3049 | ||
3050 | Note: By default, advertise-pip feature is enabled and user has an option to | |
0a4e0034 | 3051 | disable the feature via configuration CLI. Once the feature is disabled under |
b6c34e85 CS |
3052 | bgp vrf instance or MAC-VLAN interface is not configured, all the routes follow |
3053 | the same behavior of using same next-hop and RMAC values. | |
3054 | ||
03750f1e | 3055 | .. clicmd:: advertise-pip [ip <addr> [mac <addr>]] |
b6c34e85 | 3056 | |
f563acec | 3057 | Enables or disables advertise-pip feature, specify system-IP and/or system-MAC |
b6c34e85 CS |
3058 | parameters. |
3059 | ||
a927f5bc JAG |
3060 | EVPN advertise-svi-ip |
3061 | ^^^^^^^^^^^^^^^^^^^^^ | |
0a4e0034 | 3062 | Typically, the SVI IP address is reused on VTEPs across multiple racks. However, |
a927f5bc | 3063 | if you have unique SVI IP addresses that you want to be reachable you can use the |
0a4e0034 JAG |
3064 | advertise-svi-ip option. This option advertises the SVI IP/MAC address as a type-2 |
3065 | route and eliminates the need for any flooding over VXLAN to reach the IP from a | |
3066 | remote VTEP. | |
3067 | ||
a927f5bc | 3068 | .. clicmd:: advertise-svi-ip |
0a4e0034 JAG |
3069 | |
3070 | Note that you should not enable both the advertise-svi-ip and the advertise-default-gw | |
3071 | at the same time. | |
3072 | ||
40f4507d AD |
3073 | .. _bgp-evpn-overlay-index-gateway-ip: |
3074 | ||
3075 | EVPN Overlay Index Gateway IP | |
3076 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | |
d272105a MC |
3077 | RFC https://datatracker.ietf.org/doc/html/rfc9136 explains the use of overlay |
3078 | indexes for recursive route resolution for EVPN type-5 route. | |
40f4507d AD |
3079 | |
3080 | We support gateway IP overlay index. | |
3081 | A gateway IP, advertised with EVPN prefix route, is used to find an EVPN MAC/IP | |
3082 | route with its IP field same as the gateway IP. This MAC/IP entry provides the | |
3083 | nexthop VTEP and the tunnel information required for the VxLAN encapsulation. | |
3084 | ||
3085 | Functionality: | |
3086 | ||
3087 | :: | |
3088 | ||
3089 | . +--------+ BGP +--------+ BGP +--------+ +--------+ | |
3090 | SN1 | | IPv4 | | EVPN | | | | | |
3091 | ======+ Host1 +------+ PE1 +------+ PE2 +------+ Host2 + | |
3092 | | | | | | | | | | |
3093 | +--------+ +--------+ +--------+ +--------+ | |
3094 | ||
3095 | Consider above topology where prefix SN1 is connected behind host1. Host1 | |
3096 | advertises SN1 to PE1 over BGP IPv4 session. PE1 advertises SN1 to PE2 using | |
3097 | EVPN type-5 route with host1 IP as the gateway IP. PE1 also advertises | |
3098 | Host1 MAC/IP as type-2 route which is used to resolve host1 gateway IP. | |
3099 | ||
3100 | PE2 receives this type-5 route and imports it into the vrf based on route | |
3101 | targets. BGP prefix imported into the vrf uses gateway IP as its BGP nexthop. | |
3102 | This route is installed into zebra if following conditions are satisfied: | |
7aa6fb2d | 3103 | |
40f4507d AD |
3104 | 1. Gateway IP nexthop is L3 reachable. |
3105 | 2. PE2 has received EVPN type-2 route with IP field set to gateway IP. | |
3106 | ||
3107 | Topology requirements: | |
7aa6fb2d | 3108 | |
40f4507d AD |
3109 | 1. This feature is supported for asymmetric routing model only. While |
3110 | sending packets to SN1, ingress PE (PE2) performs routing and | |
3111 | egress PE (PE1) performs only bridging. | |
f563acec | 3112 | 2. This feature supports only traditional(non vlan-aware) bridge model. Bridge |
40f4507d AD |
3113 | interface associated with L2VNI is an L3 interface. i.e., this interface is |
3114 | configured with an address in the L2VNI subnet. Note that the gateway IP | |
3115 | should also have an address in the same subnet. | |
3116 | 3. As this feature works in asymmetric routing model, all L2VNIs and corresponding | |
3117 | VxLAN and bridge interfaces should be present at all the PEs. | |
3118 | 4. L3VNI configuration is required to generate and import EVPN type-5 routes. | |
3119 | L3VNI VxLAN and bridge interfaces also should be present. | |
3120 | ||
3121 | A PE can use one of the following two mechanisms to advertise an EVPN type-5 | |
3122 | route with gateway IP. | |
3123 | ||
3124 | 1. CLI to add gateway IP while generating EVPN type-5 route from a BGP IPv4/IPv6 | |
3125 | prefix: | |
3126 | ||
5c54512e | 3127 | .. clicmd:: advertise <ipv4|ipv6> unicast [gateway-ip] |
40f4507d AD |
3128 | |
3129 | When this CLI is configured for a BGP vrf under L2VPN EVPN address family, EVPN | |
3130 | type-5 routes are generated for BGP prefixes in the vrf. Nexthop of the BGP | |
3131 | prefix becomes the gateway IP of the corresponding type-5 route. | |
3132 | ||
3133 | If the above command is configured without the "gateway-ip" keyword, type-5 | |
3134 | routes are generated without overlay index. | |
3135 | ||
3136 | 2. Add gateway IP to EVPN type-5 route using a route-map: | |
3137 | ||
5c54512e | 3138 | .. clicmd:: set evpn gateway-ip <ipv4|ipv6> <addr> |
40f4507d AD |
3139 | |
3140 | When route-map with above set clause is applied as outbound policy in BGP, it | |
3141 | will set the gateway-ip in EVPN type-5 NLRI. | |
3142 | ||
3143 | Example configuration: | |
3144 | ||
3145 | .. code-block:: frr | |
3146 | ||
3147 | router bgp 100 | |
3148 | neighbor 192.168.0.1 remote-as 101 | |
3149 | ! | |
3150 | address-family ipv4 l2vpn evpn | |
3151 | neighbor 192.168.0.1 route-map RMAP out | |
3152 | exit-address-family | |
3153 | ! | |
3154 | route-map RMAP permit 10 | |
3155 | set evpn gateway-ip 10.0.0.1 | |
3156 | set evpn gateway-ip 10::1 | |
3157 | ||
3158 | A PE that receives a type-5 route with gateway IP overlay index should have | |
3159 | "enable-resolve-overlay-index" configuration enabled to recursively resolve the | |
3160 | overlay index nexthop and install the prefix into zebra. | |
3161 | ||
5c54512e | 3162 | .. clicmd:: enable-resolve-overlay-index |
40f4507d AD |
3163 | |
3164 | Example configuration: | |
3165 | ||
3166 | .. code-block:: frr | |
3167 | ||
3168 | router bgp 65001 | |
3169 | bgp router-id 192.168.100.1 | |
3170 | no bgp ebgp-requires-policy | |
3171 | neighbor 10.0.1.2 remote-as 65002 | |
3172 | ! | |
3173 | address-family l2vpn evpn | |
3174 | neighbor 10.0.1.2 activate | |
3175 | advertise-all-vni | |
3176 | enable-resolve-overlay-index | |
3177 | exit-address-family | |
3178 | ! | |
3179 | ||
92396068 AK |
3180 | .. _bgp-evpn-mh: |
3181 | ||
77457939 AK |
3182 | EVPN Multihoming |
3183 | ^^^^^^^^^^^^^^^^ | |
3184 | ||
3185 | All-Active Multihoming is used for redundancy and load sharing. Servers | |
3186 | are attached to two or more PEs and the links are bonded (link-aggregation). | |
3187 | This group of server links is referred to as an Ethernet Segment. | |
3188 | ||
3189 | Ethernet Segments | |
3190 | """"""""""""""""" | |
3191 | An Ethernet Segment can be configured by specifying a system-MAC and a | |
c52de8c1 | 3192 | local discriminator or a complete ESINAME against the bond interface on the |
3193 | PE (via zebra) - | |
77457939 | 3194 | |
c52de8c1 | 3195 | .. clicmd:: evpn mh es-id <(1-16777215)|ESINAME> |
77457939 | 3196 | |
03750f1e | 3197 | .. clicmd:: evpn mh es-sys-mac X:X:X:X:X:X |
77457939 AK |
3198 | |
3199 | The sys-mac and local discriminator are used for generating a 10-byte, | |
c52de8c1 | 3200 | Type-3 Ethernet Segment ID. ESINAME is a 10-byte, Type-0 Ethernet Segment ID - |
3201 | "00:AA:BB:CC:DD:EE:FF:GG:HH:II". | |
77457939 | 3202 | |
c12d5f20 | 3203 | Type-1 (EAD-per-ES and EAD-per-EVI) routes are used to advertise the locally |
77457939 AK |
3204 | attached ESs and to learn off remote ESs in the network. Local Type-2/MAC-IP |
3205 | routes are also advertised with a destination ESI allowing for MAC-IP syncing | |
3206 | between Ethernet Segment peers. | |
3207 | Reference: RFC 7432, RFC 8365 | |
3208 | ||
3209 | EVPN-MH is intended as a replacement for MLAG or Anycast VTEPs. In | |
3210 | multihoming each PE has an unique VTEP address which requires the introduction | |
3211 | of a new dataplane construct, MAC-ECMP. Here a MAC/FDB entry can point to a | |
3212 | list of remote PEs/VTEPs. | |
3213 | ||
3214 | BUM handling | |
3215 | """""""""""" | |
3216 | Type-4 (ESR) routes are used for Designated Forwarder (DF) election. DFs | |
3217 | forward BUM traffic received via the overlay network. This implementation | |
3218 | uses a preference based DF election specified by draft-ietf-bess-evpn-pref-df. | |
3219 | The DF preference is configurable per-ES (via zebra) - | |
3220 | ||
03750f1e | 3221 | .. clicmd:: evpn mh es-df-pref (1-16777215) |
77457939 AK |
3222 | |
3223 | BUM traffic is rxed via the overlay by all PEs attached to a server but | |
3224 | only the DF can forward the de-capsulated traffic to the access port. To | |
f563acec | 3225 | accommodate that non-DF filters are installed in the dataplane to drop |
77457939 AK |
3226 | the traffic. |
3227 | ||
3228 | Similarly traffic received from ES peers via the overlay cannot be forwarded | |
3229 | to the server. This is split-horizon-filtering with local bias. | |
3230 | ||
fe8293c3 AK |
3231 | Knobs for interop |
3232 | """"""""""""""""" | |
3233 | Some vendors do not send EAD-per-EVI routes. To interop with them we | |
3234 | need to relax the dependency on EAD-per-EVI routes and activate a remote | |
3235 | ES-PE based on just the EAD-per-ES route. | |
3236 | ||
3237 | Note that by default we advertise and expect EAD-per-EVI routes. | |
3238 | ||
03750f1e | 3239 | .. clicmd:: disable-ead-evi-rx |
fe8293c3 | 3240 | |
03750f1e | 3241 | .. clicmd:: disable-ead-evi-tx |
fe8293c3 | 3242 | |
77457939 AK |
3243 | Fast failover |
3244 | """"""""""""" | |
3245 | As the primary purpose of EVPN-MH is redundancy keeping the failover efficient | |
3246 | is a recurring theme in the implementation. Following sub-features have | |
3247 | been introduced for the express purpose of efficient ES failovers. | |
3248 | ||
3249 | - Layer-2 Nexthop Groups and MAC-ECMP via L2NHG. | |
3250 | ||
3251 | - Host routes (for symmetric IRB) via L3NHG. | |
3252 | On dataplanes that support layer3 nexthop groups the feature can be turned | |
3253 | on via the following BGP config - | |
3254 | ||
03750f1e | 3255 | .. clicmd:: use-es-l3nhg |
77457939 AK |
3256 | |
3257 | - Local ES (MAC/Neigh) failover via ES-redirect. | |
3258 | On dataplanes that do not have support for ES-redirect the feature can be | |
3259 | turned off via the following zebra config - | |
3260 | ||
03750f1e | 3261 | .. clicmd:: evpn mh redirect-off |
77457939 AK |
3262 | |
3263 | Uplink/Core tracking | |
3264 | """""""""""""""""""" | |
3265 | When all the underlay links go down the PE no longer has access to the VxLAN | |
3266 | +overlay. To prevent blackholing of traffic the server/ES links are | |
3267 | protodowned on the PE. A link can be setup for uplink tracking via the | |
3268 | following zebra configuration - | |
3269 | ||
03750f1e | 3270 | .. clicmd:: evpn mh uplink |
77457939 AK |
3271 | |
3272 | Proxy advertisements | |
3273 | """""""""""""""""""" | |
3274 | To handle hitless upgrades support for proxy advertisement has been added | |
3275 | as specified by draft-rbickhart-evpn-ip-mac-proxy-adv. This allows a PE | |
3276 | (say PE1) to proxy advertise a MAC-IP rxed from an ES peer (say PE2). When | |
3277 | the ES peer (PE2) goes down PE1 continues to advertise hosts learnt from PE2 | |
3278 | for a holdtime during which it attempts to establish local reachability of | |
3279 | the host. This holdtime is configurable via the following zebra commands - | |
3280 | ||
03750f1e | 3281 | .. clicmd:: evpn mh neigh-holdtime (0-86400) |
77457939 | 3282 | |
03750f1e | 3283 | .. clicmd:: evpn mh mac-holdtime (0-86400) |
77457939 AK |
3284 | |
3285 | Startup delay | |
3286 | """"""""""""" | |
3287 | When a switch is rebooted we wait for a brief period to allow the underlay | |
3288 | and EVPN network to converge before enabling the ESs. For this duration the | |
3289 | ES bonds are held protodown. The startup delay is configurable via the | |
3290 | following zebra command - | |
3291 | ||
03750f1e | 3292 | .. clicmd:: evpn mh startup-delay (0-3600) |
77457939 | 3293 | |
92396068 AK |
3294 | EAD-per-ES fragmentation |
3295 | """""""""""""""""""""""" | |
3296 | The EAD-per-ES route carries the EVI route targets for all the broadcast | |
3297 | domains associated with the ES. Depending on the EVI scale the EAD-per-ES | |
3298 | route maybe fragmented. | |
3299 | ||
3300 | The number of EVIs per-EAD route can be configured via the following | |
3301 | BGP command - | |
3302 | ||
c12d5f20 | 3303 | .. clicmd:: [no] ead-es-frag evi-limit (1-1000) |
92396068 AK |
3304 | |
3305 | Sample Configuration | |
3306 | ^^^^^^^^^^^^^^^^^^^^^ | |
3307 | .. code-block:: frr | |
3308 | ||
3309 | ! | |
3310 | router bgp 5556 | |
3311 | ! | |
3312 | address-family l2vpn evpn | |
3313 | ead-es-frag evi-limit 200 | |
3314 | exit-address-family | |
3315 | ! | |
3316 | ! | |
3317 | ||
3318 | EAD-per-ES route-target | |
3319 | """"""""""""""""""""""" | |
3320 | The EAD-per-ES route by default carries all the EVI route targets. Depending | |
3321 | on EVI scale that can result in route fragmentation. In some cases it maybe | |
3322 | necessary to avoid this fragmentation and that can be done via the following | |
3323 | workaround - | |
3324 | 1. Configure a single supplementary BD per-tenant VRF. This SBD needs to | |
3325 | be provisioned on all EVPN PEs associated with the tenant-VRF. | |
3326 | 2. Config the SBD's RT as the EAD-per-ES route's export RT. | |
3327 | ||
3328 | Sample Configuration | |
3329 | ^^^^^^^^^^^^^^^^^^^^^ | |
3330 | .. code-block:: frr | |
3331 | ||
3332 | ! | |
3333 | router bgp 5556 | |
3334 | ! | |
3335 | address-family l2vpn evpn | |
3336 | ead-es-route-target export 5556:1001 | |
3337 | ead-es-route-target export 5556:1004 | |
3338 | ead-es-route-target export 5556:1008 | |
3339 | exit-address-family | |
3340 | ! | |
3341 | ||
b58393f6 | 3342 | Support with VRF network namespace backend |
3343 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | |
ee9d0f09 PG |
3344 | It is possible to separate overlay networks contained in VXLAN interfaces from |
3345 | underlay networks by using VRFs. VRF-lite and VRF-netns backends can be used for | |
3346 | that. In the latter case, it is necessary to set both bridge and vxlan interface | |
3347 | in the same network namespace, as below example illustrates: | |
3348 | ||
3349 | .. code-block:: shell | |
3350 | ||
3351 | # linux shell | |
3352 | ip netns add vrf1 | |
3353 | ip link add name vxlan101 type vxlan id 101 dstport 4789 dev eth0 local 10.1.1.1 | |
3354 | ip link set dev vxlan101 netns vrf1 | |
3355 | ip netns exec vrf1 ip link set dev lo up | |
3356 | ip netns exec vrf1 brctl addbr bridge101 | |
3357 | ip netns exec vrf1 brctl addif bridge101 vxlan101 | |
3358 | ||
3359 | This makes it possible to separate not only layer 3 networks like VRF-lite networks. | |
3360 | Also, VRF netns based make possible to separate layer 2 networks on separate VRF | |
3361 | instances. | |
89b97c33 | 3362 | |
7f7940e6 MK |
3363 | .. _bgp-conditional-advertisement: |
3364 | ||
3365 | BGP Conditional Advertisement | |
3366 | ----------------------------- | |
3367 | The BGP conditional advertisement feature uses the ``non-exist-map`` or the | |
3368 | ``exist-map`` and the ``advertise-map`` keywords of the neighbor advertise-map | |
3369 | command in order to track routes by the route prefix. | |
3370 | ||
3371 | ``non-exist-map`` | |
3372 | 1. If a route prefix is not present in the output of non-exist-map command, | |
3373 | then advertise the route specified by the advertise-map command. | |
3374 | ||
3375 | 2. If a route prefix is present in the output of non-exist-map command, | |
3376 | then do not advertise the route specified by the addvertise-map command. | |
3377 | ||
3378 | ``exist-map`` | |
3379 | 1. If a route prefix is present in the output of exist-map command, | |
3380 | then advertise the route specified by the advertise-map command. | |
3381 | ||
3382 | 2. If a route prefix is not present in the output of exist-map command, | |
3383 | then do not advertise the route specified by the advertise-map command. | |
3384 | ||
3385 | This feature is useful when some prefixes are advertised to one of its peers | |
3386 | only if the information from the other peer is not present (due to failure in | |
3387 | peering session or partial reachability etc). | |
3388 | ||
3389 | The conditional BGP announcements are sent in addition to the normal | |
3390 | announcements that a BGP router sends to its peer. | |
3391 | ||
3392 | The conditional advertisement process is triggered by the BGP scanner process, | |
389e4f92 QY |
3393 | which runs every 60 by default. This means that the maximum time for the |
3394 | conditional advertisement to take effect is the value of the process timer. | |
3395 | ||
3396 | As an optimization, while the process always runs on each timer expiry, it | |
3397 | determines whether or not the conditional advertisement policy or the routing | |
3398 | table has changed; if neither have changed, no processing is necessary and the | |
3399 | scanner exits early. | |
7f7940e6 | 3400 | |
03750f1e | 3401 | .. clicmd:: neighbor A.B.C.D advertise-map NAME [exist-map|non-exist-map] NAME |
7f7940e6 | 3402 | |
fa36596c | 3403 | This command enables BGP scanner process to monitor routes specified by |
7f7940e6 | 3404 | exist-map or non-exist-map command in BGP table and conditionally advertises |
fa36596c | 3405 | the routes specified by advertise-map command. |
7f7940e6 | 3406 | |
389e4f92 QY |
3407 | .. clicmd:: bgp conditional-advertisement timer (5-240) |
3408 | ||
3409 | Set the period to rerun the conditional advertisement scanner process. The | |
3410 | default is 60 seconds. | |
3411 | ||
7f7940e6 MK |
3412 | Sample Configuration |
3413 | ^^^^^^^^^^^^^^^^^^^^^ | |
3414 | .. code-block:: frr | |
3415 | ||
fa36596c MK |
3416 | interface enp0s9 |
3417 | ip address 10.10.10.2/24 | |
3418 | ! | |
3419 | interface enp0s10 | |
3420 | ip address 10.10.20.2/24 | |
3421 | ! | |
7f7940e6 | 3422 | interface lo |
fa36596c | 3423 | ip address 203.0.113.1/32 |
7f7940e6 MK |
3424 | ! |
3425 | router bgp 2 | |
3426 | bgp log-neighbor-changes | |
3427 | no bgp ebgp-requires-policy | |
3428 | neighbor 10.10.10.1 remote-as 1 | |
3429 | neighbor 10.10.20.3 remote-as 3 | |
3430 | ! | |
3431 | address-family ipv4 unicast | |
7f7940e6 | 3432 | neighbor 10.10.10.1 soft-reconfiguration inbound |
7f7940e6 | 3433 | neighbor 10.10.20.3 soft-reconfiguration inbound |
fa36596c | 3434 | neighbor 10.10.20.3 advertise-map ADV-MAP non-exist-map EXIST-MAP |
7f7940e6 MK |
3435 | exit-address-family |
3436 | ! | |
fa36596c MK |
3437 | ip prefix-list DEFAULT seq 5 permit 192.0.2.5/32 |
3438 | ip prefix-list DEFAULT seq 10 permit 192.0.2.1/32 | |
3439 | ip prefix-list EXIST seq 5 permit 10.10.10.10/32 | |
3440 | ip prefix-list DEFAULT-ROUTE seq 5 permit 0.0.0.0/0 | |
3441 | ip prefix-list IP1 seq 5 permit 10.139.224.0/20 | |
3442 | ! | |
3443 | bgp community-list standard DC-ROUTES seq 5 permit 64952:3008 | |
3444 | bgp community-list standard DC-ROUTES seq 10 permit 64671:501 | |
3445 | bgp community-list standard DC-ROUTES seq 15 permit 64950:3009 | |
3446 | bgp community-list standard DEFAULT-ROUTE seq 5 permit 65013:200 | |
7f7940e6 | 3447 | ! |
fa36596c MK |
3448 | route-map ADV-MAP permit 10 |
3449 | match ip address prefix-list IP1 | |
7f7940e6 | 3450 | ! |
fa36596c MK |
3451 | route-map ADV-MAP permit 20 |
3452 | match community DC-ROUTES | |
3453 | ! | |
3454 | route-map EXIST-MAP permit 10 | |
3455 | match community DEFAULT-ROUTE | |
3456 | match ip address prefix-list DEFAULT-ROUTE | |
7f7940e6 MK |
3457 | ! |
3458 | ||
3459 | Sample Output | |
3460 | ^^^^^^^^^^^^^ | |
3461 | ||
fa36596c | 3462 | When default route is present in R2'2 BGP table, 10.139.224.0/20 and 192.0.2.1/32 are not advertised to R3. |
7f7940e6 MK |
3463 | |
3464 | .. code-block:: frr | |
3465 | ||
3466 | Router2# show ip bgp | |
fa36596c | 3467 | BGP table version is 20, local router ID is 203.0.113.1, vrf id 0 |
7f7940e6 MK |
3468 | Default local pref 100, local AS 2 |
3469 | Status codes: s suppressed, d damped, h history, * valid, > best, = multipath, | |
3470 | i internal, r RIB-failure, S Stale, R Removed | |
3471 | Nexthop codes: @NNN nexthop's vrf id, < announce-nh-self | |
3472 | Origin codes: i - IGP, e - EGP, ? - incomplete | |
0bcfc1a3 | 3473 | RPKI validation codes: V valid, I invalid, N Not found |
7f7940e6 | 3474 | |
fa36596c MK |
3475 | Network Next Hop Metric LocPrf Weight Path |
3476 | *> 0.0.0.0/0 10.10.10.1 0 0 1 i | |
3477 | *> 10.139.224.0/20 10.10.10.1 0 0 1 ? | |
3478 | *> 192.0.2.1/32 10.10.10.1 0 0 1 i | |
3479 | *> 192.0.2.5/32 10.10.10.1 0 0 1 i | |
7f7940e6 MK |
3480 | |
3481 | Displayed 4 routes and 4 total paths | |
fa36596c | 3482 | Router2# show ip bgp neighbors 10.10.20.3 |
7f7940e6 MK |
3483 | |
3484 | !--- Output suppressed. | |
3485 | ||
3486 | For address family: IPv4 Unicast | |
fa36596c | 3487 | Update group 7, subgroup 7 |
7f7940e6 MK |
3488 | Packet Queue length 0 |
3489 | Inbound soft reconfiguration allowed | |
3490 | Community attribute sent to this neighbor(all) | |
fa36596c MK |
3491 | Condition NON_EXIST, Condition-map *EXIST-MAP, Advertise-map *ADV-MAP, status: Withdraw |
3492 | 0 accepted prefixes | |
7f7940e6 MK |
3493 | |
3494 | !--- Output suppressed. | |
3495 | ||
fa36596c MK |
3496 | Router2# show ip bgp neighbors 10.10.20.3 advertised-routes |
3497 | BGP table version is 20, local router ID is 203.0.113.1, vrf id 0 | |
7f7940e6 MK |
3498 | Default local pref 100, local AS 2 |
3499 | Status codes: s suppressed, d damped, h history, * valid, > best, = multipath, | |
fa36596c | 3500 | i internal, r RIB-failure, S Stale, R Removed |
7f7940e6 MK |
3501 | Nexthop codes: @NNN nexthop's vrf id, < announce-nh-self |
3502 | Origin codes: i - IGP, e - EGP, ? - incomplete | |
0bcfc1a3 | 3503 | RPKI validation codes: V valid, I invalid, N Not found |
7f7940e6 | 3504 | |
fa36596c MK |
3505 | Network Next Hop Metric LocPrf Weight Path |
3506 | *> 0.0.0.0/0 0.0.0.0 0 1 i | |
3507 | *> 192.0.2.5/32 0.0.0.0 0 1 i | |
7f7940e6 | 3508 | |
fa36596c | 3509 | Total number of prefixes 2 |
7f7940e6 | 3510 | |
fa36596c | 3511 | When default route is not present in R2'2 BGP table, 10.139.224.0/20 and 192.0.2.1/32 are advertised to R3. |
7f7940e6 MK |
3512 | |
3513 | .. code-block:: frr | |
3514 | ||
3515 | Router2# show ip bgp | |
fa36596c | 3516 | BGP table version is 21, local router ID is 203.0.113.1, vrf id 0 |
7f7940e6 MK |
3517 | Default local pref 100, local AS 2 |
3518 | Status codes: s suppressed, d damped, h history, * valid, > best, = multipath, | |
3519 | i internal, r RIB-failure, S Stale, R Removed | |
3520 | Nexthop codes: @NNN nexthop's vrf id, < announce-nh-self | |
3521 | Origin codes: i - IGP, e - EGP, ? - incomplete | |
0bcfc1a3 | 3522 | RPKI validation codes: V valid, I invalid, N Not found |
7f7940e6 | 3523 | |
fa36596c MK |
3524 | Network Next Hop Metric LocPrf Weight Path |
3525 | *> 10.139.224.0/20 10.10.10.1 0 0 1 ? | |
3526 | *> 192.0.2.1/32 10.10.10.1 0 0 1 i | |
3527 | *> 192.0.2.5/32 10.10.10.1 0 0 1 i | |
7f7940e6 MK |
3528 | |
3529 | Displayed 3 routes and 3 total paths | |
7f7940e6 | 3530 | |
fa36596c | 3531 | Router2# show ip bgp neighbors 10.10.20.3 |
7f7940e6 MK |
3532 | |
3533 | !--- Output suppressed. | |
3534 | ||
3535 | For address family: IPv4 Unicast | |
fa36596c | 3536 | Update group 7, subgroup 7 |
7f7940e6 MK |
3537 | Packet Queue length 0 |
3538 | Inbound soft reconfiguration allowed | |
3539 | Community attribute sent to this neighbor(all) | |
fa36596c MK |
3540 | Condition NON_EXIST, Condition-map *EXIST-MAP, Advertise-map *ADV-MAP, status: Advertise |
3541 | 0 accepted prefixes | |
7f7940e6 MK |
3542 | |
3543 | !--- Output suppressed. | |
3544 | ||
fa36596c MK |
3545 | Router2# show ip bgp neighbors 10.10.20.3 advertised-routes |
3546 | BGP table version is 21, local router ID is 203.0.113.1, vrf id 0 | |
7f7940e6 MK |
3547 | Default local pref 100, local AS 2 |
3548 | Status codes: s suppressed, d damped, h history, * valid, > best, = multipath, | |
3549 | i internal, r RIB-failure, S Stale, R Removed | |
3550 | Nexthop codes: @NNN nexthop's vrf id, < announce-nh-self | |
3551 | Origin codes: i - IGP, e - EGP, ? - incomplete | |
0bcfc1a3 | 3552 | RPKI validation codes: V valid, I invalid, N Not found |
7f7940e6 | 3553 | |
fa36596c MK |
3554 | Network Next Hop Metric LocPrf Weight Path |
3555 | *> 10.139.224.0/20 0.0.0.0 0 1 ? | |
3556 | *> 192.0.2.1/32 0.0.0.0 0 1 i | |
3557 | *> 192.0.2.5/32 0.0.0.0 0 1 i | |
7f7940e6 MK |
3558 | |
3559 | Total number of prefixes 3 | |
fa36596c | 3560 | Router2# |
7f7940e6 | 3561 | |
2b55ff40 MK |
3562 | .. _bgp-optimal-route-reflection: |
3563 | ||
3564 | BGP Optimal Route Reflection | |
3565 | ---------------------------- | |
3566 | BGP Route Reflectors (RRs) are used to improve network scalability by reducing | |
3567 | or eliminating the need for a full-mesh of IBGP sessions. | |
3568 | ||
3569 | When a BGP RR receives multiple paths for the same IP prefix, it typically | |
3570 | selects a single best path to send for all its clients. | |
3571 | If the RR has multiple nearly-equal best paths and the tie-break is determined | |
3572 | by the next-hop cost, the RR advertises the path based on its view of next-hop | |
3573 | costs, which leads to a non-optimal routing. | |
3574 | The advertised route may differ from the path that a client would select | |
3575 | if it had the visibility of the same set of candidate paths and used | |
3576 | its own view of next-hop costs. | |
3577 | ||
3578 | Non-optimal advertisements by the RR can be a problem in hot-potato routing. | |
3579 | Hot-potato routing aims to hand off traffic to the next AS using the closest | |
3580 | possible exit point from the local AS. | |
3581 | In this context, the closest exit point implies minimum IGP cost to | |
3582 | reach the BGP next-hop. | |
3583 | ||
3584 | The BGP Optimal Route Reflection allows the RR to choose and send a different | |
3585 | best path to a different or a set of RR clients. | |
3586 | ||
3587 | A link-state protocol is required. It can be OSPF or IS-IS. | |
3588 | Current implementation of BGP ORR is based on the IGP cost to the BGP next hop, | |
3589 | and not based on some configured policy. | |
3590 | ||
3591 | RR runs Shortest Path First (SPF) calculation with the selected | |
3592 | router as the root of the tree and calculates the cost to every other router. | |
3593 | ||
3594 | This special SPF calculation with another router as the root, is referred to as | |
3595 | a Reverse SPF (rSPF). This can only be done if the RR learns all the BGP paths | |
3596 | from all the BGP border routers. | |
3597 | ||
3598 | There could be as many rSPFs run as there are RR clients. | |
3599 | This will increase the CPU load somewhat on the RR. | |
3600 | ||
3601 | Current implementation allows up to three root nodes for the rSPF calculation. | |
3602 | There is no need to configure each RR client as a root and run rSPF. | |
3603 | Current implementation allows to configure three, the primary, the secondary, | |
3604 | and the tertiary root, per set of RR clients, for redundancy purposes. | |
3605 | For the BGP ORR feature to apply to any RR client, that RR client must be | |
3606 | configured to be part of an ORR policy group. | |
3607 | ||
3608 | The BGP ORR feature is enabled per address family. | |
3609 | ||
3610 | The minimal configuration needed: | |
3611 | ||
3612 | 1. ORR needs to be enabled for specific groups of BGP neighbors. | |
3613 | 2. For each group of BGP neighbors, at least one root needs to be configured. | |
3614 | Optionally, a secondary and tertiary root can be configured. | |
3615 | 3. For OSPF, the root routers(RR clients) need additional configuration | |
3616 | to make BGP ORR work. | |
3617 | i.e. The MPLS TE configuration on the root router needs to have the minimal | |
3618 | configuration for MPLS TE enabled so that OSPF advertises the MPLS TE | |
3619 | router ID in an opaque-area LSA (type 10). | |
3620 | Once the RR has an opaque-area LSA with the MPLS TE router-ID matching the | |
3621 | configured root router address, rSPF can run and BGP on the RR can | |
3622 | advertise the optimal route. | |
3623 | ||
3624 | .. clicmd:: neighbor A.B.C.D optimal-route-reflection NAME | |
3625 | ||
3626 | This command allows the neighbor to be part of the ORR group. | |
3627 | ||
3628 | .. clicmd:: optimal-route-reflection orr-1 A.B.C.D [A.B.C.D] [A.B.C.D] | |
3629 | ||
3630 | This command creates an ORR group with a mandatory primary root | |
3631 | and optional secondary and/or tertiary roots. | |
3632 | When primary is reachable it will be the active root. | |
3633 | when primary goes down, secondary followed by tertiary takes over | |
3634 | the active root's role. | |
3635 | Always rSPF calculation runs active root as the root. | |
3636 | Which means the RR advertises the path based on active root's | |
3637 | view of next-hop costs. | |
3638 | ||
3639 | Sample Configuration | |
3640 | ^^^^^^^^^^^^^^^^^^^^ | |
3641 | ||
3642 | Sample configuration on Route Reflector | |
3643 | ||
3644 | .. code-block:: frr | |
3645 | ||
3646 | ! | |
3647 | debug ospf 8 orr | |
3648 | debug bgp optimal-route-reflection | |
3649 | ! | |
3650 | interface enp0s8 | |
3651 | ip address 10.10.68.8/24 | |
3652 | ip ospf 8 area 0 | |
3653 | exit | |
3654 | ! | |
3655 | interface lo | |
3656 | ip address 10.100.1.8/32 | |
3657 | ip ospf 8 area 0 | |
3658 | exit | |
3659 | ! | |
3660 | router bgp 1 | |
3661 | neighbor 10.100.1.1 remote-as 1 | |
3662 | neighbor 10.100.1.1 update-source lo | |
3663 | neighbor 10.100.1.2 remote-as 1 | |
3664 | neighbor 10.100.1.2 update-source lo | |
3665 | neighbor 10.100.1.3 remote-as 1 | |
3666 | neighbor 10.100.1.3 update-source lo | |
3667 | neighbor 10.100.1.4 remote-as 1 | |
3668 | neighbor 10.100.1.4 update-source lo | |
3669 | ! | |
3670 | address-family ipv4 unicast | |
3671 | neighbor 10.100.1.1 route-reflector-client | |
3672 | neighbor 10.100.1.1 optimal-route-reflection orr-1 | |
3673 | neighbor 10.100.1.2 route-reflector-client | |
3674 | neighbor 10.100.1.2 optimal-route-reflection orr-1 | |
3675 | neighbor 10.100.1.3 route-reflector-client | |
3676 | neighbor 10.100.1.3 optimal-route-reflection orr-1 | |
3677 | neighbor 10.100.1.4 route-reflector-client | |
3678 | neighbor 10.100.1.4 optimal-route-reflection orr-1 | |
3679 | optimal-route-reflection orr-1 10.100.1.4 10.100.1.3 10.100.1.1 | |
3680 | exit-address-family | |
3681 | exit | |
3682 | ! | |
3683 | router ospf 8 | |
3684 | ospf router-id 8.8.8.8 | |
3685 | area 0 authentication | |
3686 | capability opaque | |
3687 | exit | |
3688 | ! | |
3689 | end | |
3690 | ||
3691 | Sample configuration on RR clients | |
3692 | ||
3693 | .. code-block:: frr | |
3694 | ||
3695 | interface enp0s8 | |
3696 | ip address 10.10.34.4/24 | |
3697 | ip ospf 4 area 0 | |
3698 | link-params | |
3699 | enable | |
3700 | exit-link-params | |
3701 | exit | |
3702 | ! | |
3703 | interface enp0s9 | |
3704 | ip address 10.10.74.4/24 | |
3705 | ip ospf 4 area 0 | |
3706 | link-params | |
3707 | enable | |
3708 | exit-link-params | |
3709 | exit | |
3710 | ! | |
3711 | interface lo | |
3712 | ip address 10.100.1.4/32 | |
3713 | ip ospf 4 area 0 | |
3714 | exit | |
3715 | ! | |
3716 | router bgp 1 | |
3717 | neighbor 10.100.1.8 remote-as 1 | |
3718 | neighbor 10.100.1.8 update-source lo | |
3719 | ! | |
3720 | address-family ipv4 unicast | |
3721 | neighbor 10.100.1.8 soft-reconfiguration inbound | |
3722 | exit-address-family | |
3723 | exit | |
3724 | ! | |
3725 | router ospf 4 | |
3726 | ospf router-id 4.4.4.4 | |
3727 | area 0 authentication | |
3728 | capability opaque | |
3729 | mpls-te on | |
3730 | mpls-te router-address 10.100.1.4 | |
3731 | mpls-te inter-as area 0.0.0.0 | |
3732 | mpls-te export | |
3733 | exit | |
3734 | ! | |
3735 | end | |
3736 | ||
3737 | Sample Output | |
3738 | ^^^^^^^^^^^^^ | |
3739 | ||
3740 | When Optimal Route Reflection is not enabled on RR, it sends 10.100.1.1 as the best path to its clients. | |
3741 | ||
3742 | .. code-block:: frr | |
3743 | ||
3744 | Router-RR# show ip bgp neighbors 10.100.1.4 | |
3745 | ||
3746 | !--- Output suppressed. | |
3747 | ||
3748 | For address family: IPv4 Unicast | |
3749 | Update group 2, subgroup 2 | |
3750 | Packet Queue length 0 | |
3751 | Route-Reflector Client | |
3752 | Community attribute sent to this neighbor(all) | |
3753 | 0 accepted prefixes | |
3754 | ||
3755 | !--- Output suppressed. | |
3756 | ||
3757 | Router-RR# | |
3758 | Router-RR# show ip bgp | |
3759 | BGP table version is 3, local router ID is 10.100.1.8, vrf id 0 | |
3760 | Default local pref 100, local AS 1 | |
3761 | Status codes: s suppressed, d damped, h history, * valid, > best, = multipath, | |
3762 | i internal, r RIB-failure, S Stale, R Removed | |
3763 | Nexthop codes: @NNN nexthop's vrf id, < announce-nh-self | |
3764 | Origin codes: i - IGP, e - EGP, ? - incomplete | |
3765 | RPKI validation codes: V valid, I invalid, N Not found | |
3766 | ||
3767 | Network Next Hop Metric LocPrf Weight Path | |
3768 | * i203.0.113.0/24 10.100.1.2 0 100 0 i | |
3769 | *>i 10.100.1.1 0 100 0 i | |
3770 | *=i 10.100.1.3 0 100 0 i | |
3771 | ||
3772 | Displayed 1 routes and 3 total paths | |
3773 | Router-RR# | |
3774 | ||
3775 | Router-PE4# show ip bgp | |
3776 | BGP table version is 5, local router ID is 10.100.1.4, vrf id 0 | |
3777 | Default local pref 100, local AS 1 | |
3778 | Status codes: s suppressed, d damped, h history, * valid, > best, = multipath, | |
3779 | i internal, r RIB-failure, S Stale, R Removed | |
3780 | Nexthop codes: @NNN nexthop's vrf id, < announce-nh-self | |
3781 | Origin codes: i - IGP, e - EGP, ? - incomplete | |
3782 | RPKI validation codes: V valid, I invalid, N Not found | |
3783 | ||
3784 | Network Next Hop Metric LocPrf Weight Path | |
3785 | *>i203.0.113.0/24 10.100.1.1 0 100 0 i | |
3786 | ||
3787 | Displayed 1 routes and 1 total paths | |
3788 | Router-PE4# | |
3789 | ||
3790 | When Optimal Route Reflection is enabled on RR, it sends 10.100.1.3 as the best path to its clients. | |
3791 | ||
3792 | .. code-block:: frr | |
3793 | ||
3794 | Router-RR# show ip bgp neighbors 10.100.1.4 | |
3795 | ||
3796 | !--- Output suppressed. | |
3797 | ||
3798 | For address family: IPv4 Unicast | |
3799 | Update group 1, subgroup 1 | |
3800 | Packet Queue length 0 | |
3801 | Route-Reflector Client | |
3802 | ORR group (configured) : orr-1 | |
3803 | Community attribute sent to this neighbor(all) | |
3804 | 0 accepted prefixes | |
3805 | ||
3806 | !--- Output suppressed. | |
3807 | ||
3808 | Router-RR# | |
3809 | Router-RR# show ip bgp | |
3810 | BGP table version is 1, local router ID is 10.100.1.8, vrf id 0 | |
3811 | Default local pref 100, local AS 1 | |
3812 | Status codes: s suppressed, d damped, h history, * valid, > best, = multipath, | |
3813 | i internal, r RIB-failure, S Stale, R Removed | |
3814 | Nexthop codes: @NNN nexthop's vrf id, < announce-nh-self | |
3815 | Origin codes: i - IGP, e - EGP, ? - incomplete | |
3816 | RPKI validation codes: V valid, I invalid, N Not found | |
3817 | ||
3818 | Network Next Hop Metric LocPrf Weight Path | |
3819 | * i203.0.113.0/24 10.100.1.2 0 100 0 i | |
3820 | *>i 10.100.1.3 0 100 0 i | |
3821 | * i 10.100.1.1 0 100 0 i | |
3822 | ||
3823 | Displayed 1 routes and 3 total paths | |
3824 | Router-RR# | |
3825 | ||
3826 | Router-RR# show ip bgp optimal-route-reflection | |
3827 | ||
3828 | ORR group: orr-1, IPv4 Unicast | |
3829 | Configured root: primary: 10.100.1.4(Router-PE4), secondary: 10.100.1.3(Router-PE3), tertiary: 10.100.1.1(Router-PE1) | |
3830 | Active Root: 10.100.1.4(Router-PE4) | |
3831 | ||
3832 | RR Clients mapped: | |
3833 | 10.100.1.1 | |
3834 | 10.100.1.2 | |
3835 | 10.100.1.3 | |
3836 | 10.100.1.4 | |
3837 | ||
3838 | Number of mapping entries: 4 | |
3839 | ||
3840 | Prefix Cost | |
3841 | 10.10.34.0/24 100 | |
3842 | 10.10.61.0/24 300 | |
3843 | 10.10.63.0/24 200 | |
3844 | 10.10.67.0/24 200 | |
3845 | 10.10.68.0/24 300 | |
3846 | 10.10.72.0/24 200 | |
3847 | 10.10.74.0/24 100 | |
3848 | 10.100.1.1/32 300 | |
3849 | 10.100.1.2/32 200 | |
3850 | 10.100.1.3/32 100 | |
3851 | 10.100.1.4/32 0 | |
3852 | 10.100.1.6/32 200 | |
3853 | 10.100.1.7/32 100 | |
3854 | 10.100.1.8/32 300 | |
3855 | ||
3856 | Number of mapping entries: 14 | |
3857 | ||
3858 | Router-RR# | |
3859 | ||
3860 | Router-PE4# show ip bgp | |
3861 | BGP table version is 3, local router ID is 10.100.1.4, vrf id 0 | |
3862 | Default local pref 100, local AS 1 | |
3863 | Status codes: s suppressed, d damped, h history, * valid, > best, = multipath, | |
3864 | i internal, r RIB-failure, S Stale, R Removed | |
3865 | Nexthop codes: @NNN nexthop's vrf id, < announce-nh-self | |
3866 | Origin codes: i - IGP, e - EGP, ? - incomplete | |
3867 | RPKI validation codes: V valid, I invalid, N Not found | |
3868 | ||
3869 | Network Next Hop Metric LocPrf Weight Path | |
3870 | *>i203.0.113.0/24 10.100.1.3 0 100 0 i | |
3871 | ||
3872 | Displayed 1 routes and 1 total paths | |
3873 | Router-PE4# | |
3874 | ||
8fcedbd2 QY |
3875 | .. _bgp-debugging: |
3876 | ||
3877 | Debugging | |
3878 | --------- | |
42fc5d26 | 3879 | |
29adcd50 | 3880 | .. clicmd:: show debug |
42fc5d26 | 3881 | |
8fcedbd2 | 3882 | Show all enabled debugs. |
42fc5d26 | 3883 | |
54422b46 DS |
3884 | .. clicmd:: show bgp listeners |
3885 | ||
3886 | Display Listen sockets and the vrf that created them. Useful for debugging of when | |
3887 | listen is not working and this is considered a developer debug statement. | |
3888 | ||
8666265e DS |
3889 | .. clicmd:: debug bgp allow-martian |
3890 | ||
3891 | Enable or disable BGP accepting martian nexthops from a peer. Please note | |
3892 | this is not an actual debug command and this command is also being deprecated | |
3893 | and will be removed soon. The new command is :clicmd:`bgp allow-martian-nexthop` | |
3894 | ||
81313f43 RZ |
3895 | .. clicmd:: debug bgp bfd |
3896 | ||
3897 | Enable or disable debugging for BFD events. This will show BFD integration | |
3898 | library messages and BGP BFD integration messages that are mostly state | |
3899 | transitions and validation problems. | |
3900 | ||
8093d799 MK |
3901 | .. clicmd:: debug bgp conditional-advertisement |
3902 | ||
3903 | Enable or disable debugging of BGP conditional advertisement. | |
3904 | ||
03750f1e | 3905 | .. clicmd:: debug bgp neighbor-events |
42fc5d26 | 3906 | |
8fcedbd2 QY |
3907 | Enable or disable debugging for neighbor events. This provides general |
3908 | information on BGP events such as peer connection / disconnection, session | |
3909 | establishment / teardown, and capability negotiation. | |
42fc5d26 | 3910 | |
03750f1e | 3911 | .. clicmd:: debug bgp updates |
42fc5d26 | 3912 | |
8fcedbd2 QY |
3913 | Enable or disable debugging for BGP updates. This provides information on |
3914 | BGP UPDATE messages transmitted and received between local and remote | |
3915 | instances. | |
42fc5d26 | 3916 | |
03750f1e | 3917 | .. clicmd:: debug bgp keepalives |
42fc5d26 | 3918 | |
8fcedbd2 QY |
3919 | Enable or disable debugging for BGP keepalives. This provides information on |
3920 | BGP KEEPALIVE messages transmitted and received between local and remote | |
3921 | instances. | |
c1a54c05 | 3922 | |
03750f1e | 3923 | .. clicmd:: debug bgp bestpath <A.B.C.D/M|X:X::X:X/M> |
42fc5d26 | 3924 | |
8fcedbd2 | 3925 | Enable or disable debugging for bestpath selection on the specified prefix. |
42fc5d26 | 3926 | |
03750f1e | 3927 | .. clicmd:: debug bgp nht |
4da7fda3 | 3928 | |
8fcedbd2 | 3929 | Enable or disable debugging of BGP nexthop tracking. |
4da7fda3 | 3930 | |
03750f1e | 3931 | .. clicmd:: debug bgp update-groups |
4b44467c | 3932 | |
8fcedbd2 QY |
3933 | Enable or disable debugging of dynamic update groups. This provides general |
3934 | information on group creation, deletion, join and prune events. | |
4b44467c | 3935 | |
03750f1e | 3936 | .. clicmd:: debug bgp zebra |
42fc5d26 | 3937 | |
8fcedbd2 | 3938 | Enable or disable debugging of communications between *bgpd* and *zebra*. |
c3c5a71f | 3939 | |
2b55ff40 MK |
3940 | .. clicmd:: debug bgp optimal-route-reflection |
3941 | ||
3942 | Enable or disable debugging of BGP Optimal Route Reflection. | |
3943 | ||
8fcedbd2 QY |
3944 | Dumping Messages and Routing Tables |
3945 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | |
42fc5d26 | 3946 | |
8fcedbd2 | 3947 | .. clicmd:: dump bgp all PATH [INTERVAL] |
42fc5d26 | 3948 | |
8fcedbd2 | 3949 | .. clicmd:: dump bgp all-et PATH [INTERVAL] |
c3c5a71f | 3950 | |
42fc5d26 | 3951 | |
8fcedbd2 QY |
3952 | Dump all BGP packet and events to `path` file. |
3953 | If `interval` is set, a new file will be created for echo `interval` of | |
3954 | seconds. The path `path` can be set with date and time formatting | |
3955 | (strftime). The type ‘all-et’ enables support for Extended Timestamp Header | |
3956 | (:ref:`packet-binary-dump-format`). | |
c3c5a71f | 3957 | |
8fcedbd2 | 3958 | .. clicmd:: dump bgp updates PATH [INTERVAL] |
42fc5d26 | 3959 | |
8fcedbd2 | 3960 | .. clicmd:: dump bgp updates-et PATH [INTERVAL] |
42fc5d26 | 3961 | |
42fc5d26 | 3962 | |
8fcedbd2 QY |
3963 | Dump only BGP updates messages to `path` file. |
3964 | If `interval` is set, a new file will be created for echo `interval` of | |
3965 | seconds. The path `path` can be set with date and time formatting | |
3966 | (strftime). The type ‘updates-et’ enables support for Extended Timestamp | |
3967 | Header (:ref:`packet-binary-dump-format`). | |
42fc5d26 | 3968 | |
8fcedbd2 | 3969 | .. clicmd:: dump bgp routes-mrt PATH |
c3c5a71f | 3970 | |
8fcedbd2 | 3971 | .. clicmd:: dump bgp routes-mrt PATH INTERVAL |
42fc5d26 | 3972 | |
42fc5d26 | 3973 | |
8fcedbd2 QY |
3974 | Dump whole BGP routing table to `path`. This is heavy process. The path |
3975 | `path` can be set with date and time formatting (strftime). If `interval` is | |
3976 | set, a new file will be created for echo `interval` of seconds. | |
42fc5d26 | 3977 | |
8fcedbd2 | 3978 | Note: the interval variable can also be set using hours and minutes: 04h20m00. |
42fc5d26 | 3979 | |
c3c5a71f | 3980 | |
8fcedbd2 | 3981 | .. _bgp-other-commands: |
42fc5d26 | 3982 | |
8fcedbd2 QY |
3983 | Other BGP Commands |
3984 | ------------------ | |
42fc5d26 | 3985 | |
e312b6c6 QY |
3986 | The following are available in the top level *enable* mode: |
3987 | ||
dc912615 DS |
3988 | .. clicmd:: clear bgp \* |
3989 | ||
3990 | Clear all peers. | |
3991 | ||
8fcedbd2 | 3992 | .. clicmd:: clear bgp ipv4|ipv6 \* |
42fc5d26 | 3993 | |
dc912615 DS |
3994 | Clear all peers with this address-family activated. |
3995 | ||
dc912615 DS |
3996 | .. clicmd:: clear bgp ipv4|ipv6 unicast \* |
3997 | ||
3998 | Clear all peers with this address-family and sub-address-family activated. | |
42fc5d26 | 3999 | |
8fcedbd2 | 4000 | .. clicmd:: clear bgp ipv4|ipv6 PEER |
42fc5d26 | 4001 | |
dc912615 DS |
4002 | Clear peers with address of X.X.X.X and this address-family activated. |
4003 | ||
dc912615 DS |
4004 | .. clicmd:: clear bgp ipv4|ipv6 unicast PEER |
4005 | ||
4006 | Clear peer with address of X.X.X.X and this address-family and sub-address-family activated. | |
4007 | ||
dc912615 DS |
4008 | .. clicmd:: clear bgp ipv4|ipv6 PEER soft|in|out |
4009 | ||
4010 | Clear peer using soft reconfiguration in this address-family. | |
42fc5d26 | 4011 | |
dc912615 | 4012 | .. clicmd:: clear bgp ipv4|ipv6 unicast PEER soft|in|out |
42fc5d26 | 4013 | |
dc912615 | 4014 | Clear peer using soft reconfiguration in this address-family and sub-address-family. |
42fc5d26 | 4015 | |
33bbb2e7 DS |
4016 | .. clicmd:: clear bgp [ipv4|ipv6] [unicast] PEER|\* message-stats |
4017 | ||
4018 | Clear BGP message statistics for a specified peer or for all peers, | |
4019 | optionally filtered by activated address-family and sub-address-family. | |
4020 | ||
e312b6c6 QY |
4021 | The following are available in the ``router bgp`` mode: |
4022 | ||
e312b6c6 QY |
4023 | .. clicmd:: write-quanta (1-64) |
4024 | ||
4025 | BGP message Tx I/O is vectored. This means that multiple packets are written | |
4026 | to the peer socket at the same time each I/O cycle, in order to minimize | |
4027 | system call overhead. This value controls how many are written at a time. | |
4028 | Under certain load conditions, reducing this value could make peer traffic | |
4029 | less 'bursty'. In practice, leave this settings on the default (64) unless | |
4030 | you truly know what you are doing. | |
4031 | ||
dad83b67 | 4032 | .. clicmd:: read-quanta (1-10) |
e312b6c6 QY |
4033 | |
4034 | Unlike Tx, BGP Rx traffic is not vectored. Packets are read off the wire one | |
4035 | at a time in a loop. This setting controls how many iterations the loop runs | |
4036 | for. As with write-quanta, it is best to leave this setting on the default. | |
42fc5d26 | 4037 | |
05bd726c | 4038 | The following command is available in ``config`` mode as well as in the |
4039 | ``router bgp`` mode: | |
4040 | ||
05bd726c | 4041 | .. clicmd:: bgp graceful-shutdown |
4042 | ||
4043 | The purpose of this command is to initiate BGP Graceful Shutdown which | |
4044 | is described in :rfc:`8326`. The use case for this is to minimize or | |
4045 | eliminate the amount of traffic loss in a network when a planned | |
4046 | maintenance activity such as software upgrade or hardware replacement | |
4047 | is to be performed on a router. The feature works by re-announcing | |
4048 | routes to eBGP peers with the GRACEFUL_SHUTDOWN community included. | |
4049 | Peers are then expected to treat such paths with the lowest preference. | |
4050 | This happens automatically on a receiver running FRR; with other | |
4051 | routing protocol stacks, an inbound policy may have to be configured. | |
4052 | In FRR, triggering graceful shutdown also results in announcing a | |
4053 | LOCAL_PREF of 0 to iBGP peers. | |
4054 | ||
4055 | Graceful shutdown can be configured per BGP instance or globally for | |
4056 | all of BGP. These two options are mutually exclusive. The no form of | |
4057 | the command causes graceful shutdown to be stopped, and routes will | |
4058 | be re-announced without the GRACEFUL_SHUTDOWN community and/or with | |
4059 | the usual LOCAL_PREF value. Note that if this option is saved to | |
4060 | the startup configuration, graceful shutdown will remain in effect | |
4061 | across restarts of *bgpd* and will need to be explicitly disabled. | |
4062 | ||
a0b937de SW |
4063 | .. clicmd:: bgp input-queue-limit (1-4294967295) |
4064 | ||
4065 | Set the BGP Input Queue limit for all peers when messaging parsing. Increase | |
4066 | this only if you have the memory to handle large queues of messages at once. | |
4067 | ||
8fcedbd2 | 4068 | .. _bgp-displaying-bgp-information: |
42fc5d26 | 4069 | |
8fcedbd2 QY |
4070 | Displaying BGP Information |
4071 | ========================== | |
42fc5d26 | 4072 | |
e6f59415 PG |
4073 | The following four commands display the IPv6 and IPv4 routing tables, depending |
4074 | on whether or not the ``ip`` keyword is used. | |
4075 | Actually, :clicmd:`show ip bgp` command was used on older `Quagga` routing | |
4076 | daemon project, while :clicmd:`show bgp` command is the new format. The choice | |
4077 | has been done to keep old format with IPv4 routing table, while new format | |
4078 | displays IPv6 routing table. | |
4079 | ||
4c92d818 | 4080 | .. clicmd:: show ip bgp [all] [wide|json [detail]] |
42fc5d26 | 4081 | |
96f3485c | 4082 | .. clicmd:: show ip bgp A.B.C.D [json] |
c1a54c05 | 4083 | |
4c92d818 | 4084 | .. clicmd:: show bgp [all] [wide|json [detail]] |
e6f59415 | 4085 | |
96f3485c | 4086 | .. clicmd:: show bgp X:X::X:X [json] |
42fc5d26 | 4087 | |
8fcedbd2 | 4088 | These commands display BGP routes. When no route is specified, the default |
e6f59415 | 4089 | is to display all BGP routes. |
42fc5d26 | 4090 | |
8fcedbd2 | 4091 | :: |
c1a54c05 | 4092 | |
8fcedbd2 QY |
4093 | BGP table version is 0, local router ID is 10.1.1.1 |
4094 | Status codes: s suppressed, d damped, h history, * valid, > best, i - internal | |
4095 | Origin codes: i - IGP, e - EGP, ? - incomplete | |
42fc5d26 | 4096 | |
8fcedbd2 QY |
4097 | Network Next Hop Metric LocPrf Weight Path |
4098 | \*> 1.1.1.1/32 0.0.0.0 0 32768 i | |
42fc5d26 | 4099 | |
8fcedbd2 | 4100 | Total number of prefixes 1 |
4da7fda3 | 4101 | |
56c07345 | 4102 | If ``wide`` option is specified, then the prefix table's width is increased |
986b0fc3 DA |
4103 | to fully display the prefix and the nexthop. |
4104 | ||
4105 | This is especially handy dealing with IPv6 prefixes and | |
4106 | if :clicmd:`[no] bgp default show-nexthop-hostname` is enabled. | |
4107 | ||
56c07345 | 4108 | If ``all`` option is specified, ``ip`` keyword is ignored, show bgp all and |
96f3485c MK |
4109 | show ip bgp all commands display routes for all AFIs and SAFIs. |
4110 | ||
56c07345 | 4111 | If ``json`` option is specified, output is displayed in JSON format. |
96f3485c | 4112 | |
4c92d818 DA |
4113 | If ``detail`` option is specified after ``json``, more verbose JSON output |
4114 | will be displayed. | |
4115 | ||
e6f59415 PG |
4116 | Some other commands provide additional options for filtering the output. |
4117 | ||
e6f59415 | 4118 | .. clicmd:: show [ip] bgp regexp LINE |
42fc5d26 | 4119 | |
8fcedbd2 QY |
4120 | This command displays BGP routes using AS path regular expression |
4121 | (:ref:`bgp-regular-expressions`). | |
42fc5d26 | 4122 | |
28b25b6b | 4123 | .. clicmd:: show [ip] bgp [all] summary [wide] [json] |
42fc5d26 | 4124 | |
8fcedbd2 | 4125 | Show a bgp peer summary for the specified address family. |
42fc5d26 | 4126 | |
e6f59415 PG |
4127 | The old command structure :clicmd:`show ip bgp` may be removed in the future |
4128 | and should no longer be used. In order to reach the other BGP routing tables | |
4129 | other than the IPv6 routing table given by :clicmd:`show bgp`, the new command | |
4130 | structure is extended with :clicmd:`show bgp [afi] [safi]`. | |
4131 | ||
28b25b6b DA |
4132 | ``wide`` option gives more output like ``LocalAS`` and extended ``Desc`` to |
4133 | 64 characters. | |
4134 | ||
4135 | .. code-block:: frr | |
4136 | ||
4137 | exit1# show ip bgp summary wide | |
4138 | ||
6cac2fcc | 4139 | IPv4 Unicast Summary (VRF default): |
28b25b6b DA |
4140 | BGP router identifier 192.168.100.1, local AS number 65534 vrf-id 0 |
4141 | BGP table version 3 | |
4142 | RIB entries 5, using 920 bytes of memory | |
4143 | Peers 1, using 27 KiB of memory | |
4144 | ||
4145 | Neighbor V AS LocalAS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd PfxSnt Desc | |
4146 | 192.168.0.2 4 65030 123 15 22 0 0 0 00:07:00 0 1 us-east1-rs1.frrouting.org | |
4147 | ||
4148 | Total number of neighbors 1 | |
4149 | exit1# | |
4150 | ||
96f3485c | 4151 | .. clicmd:: show bgp [afi] [safi] [all] [wide|json] |
e6f59415 | 4152 | |
22bfb2a6 | 4153 | .. clicmd:: show bgp [<ipv4|ipv6> <unicast|multicast|vpn|labeled-unicast|flowspec> | l2vpn evpn] |
e6f59415 PG |
4154 | |
4155 | These commands display BGP routes for the specific routing table indicated by | |
4156 | the selected afi and the selected safi. If no afi and no safi value is given, | |
6cfd16ad | 4157 | the command falls back to the default IPv6 routing table. |
6cfd16ad | 4158 | |
6cfd16ad TA |
4159 | .. clicmd:: show bgp l2vpn evpn route [type <macip|2|multicast|3|es|4|prefix|5>] |
4160 | ||
22bfb2a6 | 4161 | EVPN prefixes can also be filtered by EVPN route type. |
e6f59415 | 4162 | |
8476d11c SW |
4163 | .. clicmd:: show bgp vni <all|VNI> [vtep VTEP] [type <ead|1|macip|2|multicast|3>] [<detail|json>] |
4164 | ||
4165 | Display per-VNI EVPN routing table in bgp. Filter route-type, vtep, or VNI. | |
4166 | ||
96f3485c | 4167 | .. clicmd:: show bgp [afi] [safi] [all] summary [json] |
e6f59415 PG |
4168 | |
4169 | Show a bgp peer summary for the specified address family, and subsequent | |
4170 | address-family. | |
4171 | ||
96f3485c | 4172 | .. clicmd:: show bgp [afi] [safi] [all] summary failed [json] |
3577f1c5 | 4173 | |
f563acec | 4174 | Show a bgp peer summary for peers that are not successfully exchanging routes |
3577f1c5 DD |
4175 | for the specified address family, and subsequent address-family. |
4176 | ||
96f3485c | 4177 | .. clicmd:: show bgp [afi] [safi] [all] summary established [json] |
1c027267 | 4178 | |
f563acec | 4179 | Show a bgp peer summary for peers that are successfully exchanging routes |
1c027267 DA |
4180 | for the specified address family, and subsequent address-family. |
4181 | ||
8c1d4cd5 LS |
4182 | .. clicmd:: show bgp [afi] [safi] [all] summary neighbor [PEER] [json] |
4183 | ||
4184 | Show a bgp summary for the specified peer, address family, and | |
4185 | subsequent address-family. The neighbor filter can be used in combination | |
4186 | with the failed, established filters. | |
4187 | ||
4188 | .. clicmd:: show bgp [afi] [safi] [all] summary remote-as <internal|external|ASN> [json] | |
4189 | ||
4190 | Show a bgp peer summary for the specified remote-as ASN or type (``internal`` | |
4191 | for iBGP and ``external`` for eBGP sessions), address family, and subsequent | |
4192 | address-family. The remote-as filter can be used in combination with the | |
4193 | failed, established filters. | |
4194 | ||
96c81f66 LS |
4195 | .. clicmd:: show bgp [afi] [safi] [all] summary terse [json] |
4196 | ||
4197 | Shorten the output. Do not show the following information about the BGP | |
4198 | instances: the number of RIB entries, the table version and the used memory. | |
4199 | The ``terse`` option can be used in combination with the remote-as, neighbor, | |
4200 | failed and established filters, and with the ``wide`` option as well. | |
4201 | ||
22bfb2a6 | 4202 | .. clicmd:: show bgp [afi] [safi] [neighbor [PEER] [routes|advertised-routes|received-routes] [json] |
9eb95b3b | 4203 | |
e6f59415 PG |
4204 | This command shows information on a specific BGP peer of the relevant |
4205 | afi and safi selected. | |
c1a54c05 | 4206 | |
22bfb2a6 TA |
4207 | The ``routes`` keyword displays only routes in this address-family's BGP |
4208 | table that were received by this peer and accepted by inbound policy. | |
4209 | ||
4210 | The ``advertised-routes`` keyword displays only the routes in this | |
4211 | address-family's BGP table that were permitted by outbound policy and | |
4212 | advertised to to this peer. | |
4213 | ||
4214 | The ``received-routes`` keyword displays all routes belonging to this | |
4215 | address-family (prior to inbound policy) that were received by this peer. | |
4216 | ||
d3120452 IR |
4217 | .. clicmd:: show bgp [<view|vrf> VIEWVRFNAME] [afi] [safi] neighbors PEER received prefix-filter [json] |
4218 | ||
4219 | Display Address Prefix ORFs received from this peer. | |
4220 | ||
96f3485c | 4221 | .. clicmd:: show bgp [afi] [safi] [all] dampening dampened-paths [wide|json] |
42fc5d26 | 4222 | |
e6f59415 PG |
4223 | Display paths suppressed due to dampening of the selected afi and safi |
4224 | selected. | |
42fc5d26 | 4225 | |
96f3485c | 4226 | .. clicmd:: show bgp [afi] [safi] [all] dampening flap-statistics [wide|json] |
c1a54c05 | 4227 | |
e6f59415 | 4228 | Display flap statistics of routes of the selected afi and safi selected. |
42fc5d26 | 4229 | |
fe0f234d RW |
4230 | .. clicmd:: show bgp [afi] [safi] [all] dampening parameters [json] |
4231 | ||
4232 | Display details of configured dampening parameters of the selected afi and | |
4233 | safi. | |
4234 | ||
4235 | If the ``json`` option is specified, output is displayed in JSON format. | |
4236 | ||
244e6cab DA |
4237 | .. clicmd:: show bgp [afi] [safi] [all] version (1-4294967295) [wide|json] |
4238 | ||
4239 | Display prefixes with matching version numbers. The version number and | |
4240 | above having prefixes will be listed here. | |
4241 | ||
4242 | It helps to identify which prefixes were installed at some point. | |
4243 | ||
4244 | Here is an example of how to check what prefixes were installed starting | |
05653f49 | 4245 | with an arbitrary version: |
244e6cab | 4246 | |
01af2696 | 4247 | .. code-block:: shell |
244e6cab | 4248 | |
01af2696 DS |
4249 | # vtysh -c 'show bgp ipv4 unicast json' | jq '.tableVersion' |
4250 | 9 | |
4251 | # vtysh -c 'show ip bgp version 9 json' | jq -r '.routes | keys[]' | |
4252 | 192.168.3.0/24 | |
4253 | # vtysh -c 'show ip bgp version 8 json' | jq -r '.routes | keys[]' | |
4254 | 192.168.2.0/24 | |
4255 | 192.168.3.0/24 | |
244e6cab | 4256 | |
620e23e8 PG |
4257 | .. clicmd:: show bgp [afi] [safi] statistics |
4258 | ||
4259 | Display statistics of routes of the selected afi and safi. | |
4260 | ||
620e23e8 PG |
4261 | .. clicmd:: show bgp statistics-all |
4262 | ||
4263 | Display statistics of routes of all the afi and safi. | |
4264 | ||
96f3485c MK |
4265 | .. clicmd:: show [ip] bgp [afi] [safi] [all] cidr-only [wide|json] |
4266 | ||
4267 | Display routes with non-natural netmasks. | |
4268 | ||
6deaf579 RW |
4269 | .. clicmd:: show [ip] bgp [afi] [safi] [all] prefix-list WORD [wide|json] |
4270 | ||
4271 | Display routes that match the specified prefix-list. | |
4272 | ||
4273 | If ``wide`` option is specified, then the prefix table's width is increased | |
4274 | to fully display the prefix and the nexthop. | |
4275 | ||
4276 | If the ``json`` option is specified, output is displayed in JSON format. | |
4277 | ||
61216286 DA |
4278 | .. clicmd:: show [ip] bgp [afi] [safi] [all] access-list WORD [wide|json] |
4279 | ||
4280 | Display routes that match the specified access-list. | |
4281 | ||
a7129347 RW |
4282 | .. clicmd:: show [ip] bgp [afi] [safi] [all] filter-list WORD [wide|json] |
4283 | ||
4284 | Display routes that match the specified AS-Path filter-list. | |
4285 | ||
4286 | If ``wide`` option is specified, then the prefix table's width is increased | |
4287 | to fully display the prefix and the nexthop. | |
4288 | ||
4289 | If the ``json`` option is specified, output is displayed in JSON format. | |
4290 | ||
bf1a944a RW |
4291 | .. clicmd:: show [ip] bgp [afi] [safi] [all] route-map WORD [wide|json] |
4292 | ||
4293 | Display routes that match the specified route-map. | |
4294 | ||
4295 | If ``wide`` option is specified, then the prefix table's width is increased | |
4296 | to fully display the prefix and the nexthop. | |
4297 | ||
4298 | If the ``json`` option is specified, output is displayed in JSON format. | |
4299 | ||
39c3c736 RW |
4300 | .. clicmd:: show [ip] bgp [afi] [safi] [all] <A.B.C.D/M|X:X::X:X/M> longer-prefixes [wide|json] |
4301 | ||
4302 | Displays the specified route and all more specific routes. | |
4303 | ||
4304 | If ``wide`` option is specified, then the prefix table's width is increased | |
4305 | to fully display the prefix and the nexthop. | |
4306 | ||
4307 | If the ``json`` option is specified, output is displayed in JSON format. | |
4308 | ||
96f3485c MK |
4309 | .. clicmd:: show [ip] bgp [afi] [safi] [all] neighbors A.B.C.D [advertised-routes|received-routes|filtered-routes] [json|wide] |
4310 | ||
4311 | Display the routes advertised to a BGP neighbor or received routes | |
4312 | from neighbor or filtered routes received from neighbor based on the | |
4313 | option specified. | |
4314 | ||
56c07345 | 4315 | If ``wide`` option is specified, then the prefix table's width is increased |
96f3485c MK |
4316 | to fully display the prefix and the nexthop. |
4317 | ||
4318 | This is especially handy dealing with IPv6 prefixes and | |
4319 | if :clicmd:`[no] bgp default show-nexthop-hostname` is enabled. | |
4320 | ||
56c07345 | 4321 | If ``all`` option is specified, ``ip`` keyword is ignored and, |
96f3485c | 4322 | routes displayed for all AFIs and SAFIs. |
56c07345 | 4323 | if afi is specified, with ``all`` option, routes will be displayed for |
96f3485c MK |
4324 | each SAFI in the selcted AFI |
4325 | ||
56c07345 | 4326 | If ``json`` option is specified, output is displayed in JSON format. |
96f3485c | 4327 | |
711835d9 DA |
4328 | .. clicmd:: show [ip] bgp [afi] [safi] [all] detail-routes |
4329 | ||
4330 | Display the detailed version of all routes. The same format as using | |
4331 | ``show [ip] bgp [afi] [safi] PREFIX``, but for the whole BGP table. | |
4332 | ||
4333 | If ``all`` option is specified, ``ip`` keyword is ignored and, | |
4334 | routes displayed for all AFIs and SAFIs. | |
4335 | ||
4336 | If ``afi`` is specified, with ``all`` option, routes will be displayed for | |
4337 | each SAFI in the selected AFI. | |
4338 | ||
8fcedbd2 | 4339 | .. _bgp-display-routes-by-community: |
42fc5d26 | 4340 | |
8fcedbd2 QY |
4341 | Displaying Routes by Community Attribute |
4342 | ---------------------------------------- | |
42fc5d26 | 4343 | |
8fcedbd2 QY |
4344 | The following commands allow displaying routes based on their community |
4345 | attribute. | |
42fc5d26 | 4346 | |
96f3485c | 4347 | .. clicmd:: show [ip] bgp <ipv4|ipv6> [all] community [wide|json] |
42fc5d26 | 4348 | |
96f3485c | 4349 | .. clicmd:: show [ip] bgp <ipv4|ipv6> [all] community COMMUNITY [wide|json] |
42fc5d26 | 4350 | |
96f3485c | 4351 | .. clicmd:: show [ip] bgp <ipv4|ipv6> [all] community COMMUNITY exact-match [wide|json] |
76bd1499 | 4352 | |
8fcedbd2 QY |
4353 | These commands display BGP routes which have the community attribute. |
4354 | attribute. When ``COMMUNITY`` is specified, BGP routes that match that | |
4355 | community are displayed. When `exact-match` is specified, it display only | |
4356 | routes that have an exact match. | |
c3c5a71f | 4357 | |
70799983 | 4358 | .. clicmd:: show [ip] bgp <ipv4|ipv6> community-list WORD [json] |
42fc5d26 | 4359 | |
70799983 | 4360 | .. clicmd:: show [ip] bgp <ipv4|ipv6> community-list WORD exact-match [json] |
42fc5d26 | 4361 | |
8fcedbd2 QY |
4362 | These commands display BGP routes for the address family specified that |
4363 | match the specified community list. When `exact-match` is specified, it | |
4364 | displays only routes that have an exact match. | |
42fc5d26 | 4365 | |
56c07345 | 4366 | If ``wide`` option is specified, then the prefix table's width is increased |
96f3485c MK |
4367 | to fully display the prefix and the nexthop. |
4368 | ||
4369 | This is especially handy dealing with IPv6 prefixes and | |
4370 | if :clicmd:`[no] bgp default show-nexthop-hostname` is enabled. | |
4371 | ||
56c07345 | 4372 | If ``all`` option is specified, ``ip`` keyword is ignored and, |
96f3485c | 4373 | routes displayed for all AFIs and SAFIs. |
56c07345 | 4374 | if afi is specified, with ``all`` option, routes will be displayed for |
96f3485c MK |
4375 | each SAFI in the selcted AFI |
4376 | ||
56c07345 | 4377 | If ``json`` option is specified, output is displayed in JSON format. |
e3ea6503 | 4378 | |
e3ea6503 PR |
4379 | .. clicmd:: show bgp labelpool <chunks|inuse|ledger|requests|summary> [json] |
4380 | ||
4381 | These commands display information about the BGP labelpool used for | |
4382 | the association of MPLS labels with routes for L3VPN and Labeled Unicast | |
4383 | ||
4384 | If ``chunks`` option is specified, output shows the current list of label | |
4385 | chunks granted to BGP by Zebra, indicating the start and end label in | |
4386 | each chunk | |
4387 | ||
4388 | If ``inuse`` option is specified, output shows the current inuse list of | |
4389 | label to prefix mappings | |
4390 | ||
4391 | If ``ledger`` option is specified, output shows ledger list of all | |
4392 | label requests made per prefix | |
4393 | ||
4394 | If ``requests`` option is specified, output shows current list of label | |
4395 | requests which have not yet been fulfilled by the labelpool | |
4396 | ||
4397 | If ``summary`` option is specified, output is a summary of the counts for | |
4398 | the chunks, inuse, ledger and requests list along with the count of | |
f563acec | 4399 | outstanding chunk requests to Zebra and the number of zebra reconnects |
e3ea6503 PR |
4400 | that have happened |
4401 | ||
4402 | If ``json`` option is specified, output is displayed in JSON format. | |
96f3485c | 4403 | |
36a206db | 4404 | .. _bgp-display-routes-by-lcommunity: |
4405 | ||
4406 | Displaying Routes by Large Community Attribute | |
4407 | ---------------------------------------------- | |
4408 | ||
ac2201bb | 4409 | The following commands allow displaying routes based on their |
36a206db | 4410 | large community attribute. |
4411 | ||
36a206db | 4412 | .. clicmd:: show [ip] bgp <ipv4|ipv6> large-community |
4413 | ||
36a206db | 4414 | .. clicmd:: show [ip] bgp <ipv4|ipv6> large-community LARGE-COMMUNITY |
4415 | ||
36a206db | 4416 | .. clicmd:: show [ip] bgp <ipv4|ipv6> large-community LARGE-COMMUNITY exact-match |
4417 | ||
36a206db | 4418 | .. clicmd:: show [ip] bgp <ipv4|ipv6> large-community LARGE-COMMUNITY json |
4419 | ||
4420 | These commands display BGP routes which have the large community attribute. | |
4421 | attribute. When ``LARGE-COMMUNITY`` is specified, BGP routes that match that | |
ac2201bb DA |
4422 | large community are displayed. When `exact-match` is specified, it display |
4423 | only routes that have an exact match. When `json` is specified, it display | |
36a206db | 4424 | routes in json format. |
4425 | ||
36a206db | 4426 | .. clicmd:: show [ip] bgp <ipv4|ipv6> large-community-list WORD |
4427 | ||
36a206db | 4428 | .. clicmd:: show [ip] bgp <ipv4|ipv6> large-community-list WORD exact-match |
4429 | ||
36a206db | 4430 | .. clicmd:: show [ip] bgp <ipv4|ipv6> large-community-list WORD json |
4431 | ||
4432 | These commands display BGP routes for the address family specified that | |
ac2201bb DA |
4433 | match the specified large community list. When `exact-match` is specified, |
4434 | it displays only routes that have an exact match. When `json` is specified, | |
36a206db | 4435 | it display routes in json format. |
4436 | ||
8fcedbd2 | 4437 | .. _bgp-display-routes-by-as-path: |
42fc5d26 | 4438 | |
36a206db | 4439 | |
8fcedbd2 QY |
4440 | Displaying Routes by AS Path |
4441 | ---------------------------- | |
42fc5d26 | 4442 | |
8fcedbd2 | 4443 | .. clicmd:: show bgp ipv4|ipv6 regexp LINE |
76bd1499 | 4444 | |
8fcedbd2 QY |
4445 | This commands displays BGP routes that matches a regular |
4446 | expression `line` (:ref:`bgp-regular-expressions`). | |
4447 | ||
e6f59415 | 4448 | .. clicmd:: show [ip] bgp ipv4 vpn |
8fcedbd2 | 4449 | |
e6f59415 | 4450 | .. clicmd:: show [ip] bgp ipv6 vpn |
8fcedbd2 QY |
4451 | |
4452 | Print active IPV4 or IPV6 routes advertised via the VPN SAFI. | |
4453 | ||
8fcedbd2 QY |
4454 | .. clicmd:: show bgp ipv4 vpn summary |
4455 | ||
8fcedbd2 QY |
4456 | .. clicmd:: show bgp ipv6 vpn summary |
4457 | ||
4458 | Print a summary of neighbor connections for the specified AFI/SAFI combination. | |
4459 | ||
22bfb2a6 TA |
4460 | Displaying Routes by Route Distinguisher |
4461 | ---------------------------------------- | |
4462 | ||
4463 | .. clicmd:: show bgp [<ipv4|ipv6> vpn | l2vpn evpn [route]] rd <all|RD> | |
4464 | ||
4465 | For L3VPN and EVPN address-families, routes can be displayed on a per-RD | |
4466 | (Route Distinguisher) basis or for all RD's. | |
4467 | ||
4468 | .. clicmd:: show bgp l2vpn evpn rd <all|RD> [overlay | tags] | |
4469 | ||
4470 | Use the ``overlay`` or ``tags`` keywords to display the overlay/tag | |
4471 | information about the EVPN prefixes in the selected Route Distinguisher. | |
4472 | ||
4473 | .. clicmd:: show bgp l2vpn evpn route rd <all|RD> mac <MAC> [ip <MAC>] [json] | |
4474 | ||
4475 | For EVPN Type 2 (macip) routes, a MAC address (and optionally an IP address) | |
4476 | can be supplied to the command to only display matching prefixes in the | |
4477 | specified RD. | |
4478 | ||
09d78f10 DS |
4479 | Displaying Update Group Information |
4480 | ----------------------------------- | |
4481 | ||
6c5be52a | 4482 | .. clicmd:: show bgp update-groups [advertise-queue|advertised-routes|packet-queue] |
09d78f10 DS |
4483 | |
4484 | Display Information about each individual update-group being used. | |
4485 | If SUBGROUP-ID is specified only display about that particular group. If | |
4486 | advertise-queue is specified the list of routes that need to be sent | |
4487 | to the peers in the update-group is displayed, advertised-routes means | |
a64e0ee5 | 4488 | the list of routes we have sent to the peers in the update-group and |
09d78f10 DS |
4489 | packet-queue specifies the list of packets in the queue to be sent. |
4490 | ||
6c5be52a | 4491 | .. clicmd:: show bgp update-groups statistics |
09d78f10 DS |
4492 | |
4493 | Display Information about update-group events in FRR. | |
8fcedbd2 | 4494 | |
bf85e4c5 PJD |
4495 | Displaying Nexthop Information |
4496 | -------------------- | |
071ec807 PJD |
4497 | .. clicmd:: show [ip] bgp [<view|vrf> VIEWVRFNAME] nexthop ipv4 [A.B.C.D] [detail] [json] |
4498 | ||
4499 | .. clicmd:: show [ip] bgp [<view|vrf> VIEWVRFNAME] nexthop ipv6 [X:X::X:X] [detail] [json] | |
bf85e4c5 PJD |
4500 | |
4501 | .. clicmd:: show [ip] bgp [<view|vrf> VIEWVRFNAME] nexthop [<A.B.C.D|X:X::X:X>] [detail] [json] | |
4502 | ||
4503 | .. clicmd:: show [ip] bgp <view|vrf> all nexthop [json] | |
4504 | ||
4505 | Display information about nexthops to bgp neighbors. If a certain nexthop is | |
4506 | specified, also provides information about paths associated with the nexthop. | |
4507 | With detail option provides information about gates of each nexthop. | |
4508 | ||
4509 | .. clicmd:: show [ip] bgp [<view|vrf> VIEWVRFNAME] import-check-table [detail] [json] | |
4510 | ||
4511 | Display information about nexthops from table that is used to check network's | |
4512 | existence in the rib for network statements. | |
4513 | ||
4ccd4033 HS |
4514 | Segment-Routing IPv6 |
4515 | -------------------- | |
4516 | ||
4517 | .. clicmd:: show bgp segment-routing srv6 | |
4518 | ||
4519 | This command displays information about SRv6 L3VPN in bgpd. Specifically, | |
4520 | what kind of Locator is being used, and its Locator chunk information. | |
4521 | And the SID of the SRv6 Function that is actually managed on bgpd. | |
4522 | In the following example, bgpd is using a Locator named loc1, and two SRv6 | |
4523 | Functions are managed to perform VPNv6 VRF redirect for vrf10 and vrf20. | |
4524 | ||
4525 | :: | |
4526 | ||
4527 | router# show bgp segment-routing srv6 | |
4528 | locator_name: loc1 | |
4529 | locator_chunks: | |
4530 | - 2001:db8:1:1::/64 | |
4531 | functions: | |
4532 | - sid: 2001:db8:1:1::100 | |
4533 | locator: loc1 | |
4534 | - sid: 2001:db8:1:1::200 | |
4535 | locator: loc1 | |
4536 | bgps: | |
4537 | - name: default | |
4538 | vpn_policy[AFI_IP].tovpn_sid: none | |
4539 | vpn_policy[AFI_IP6].tovpn_sid: none | |
4540 | - name: vrf10 | |
4541 | vpn_policy[AFI_IP].tovpn_sid: none | |
4542 | vpn_policy[AFI_IP6].tovpn_sid: 2001:db8:1:1::100 | |
4543 | - name: vrf20 | |
4544 | vpn_policy[AFI_IP].tovpn_sid: none | |
4545 | vpn_policy[AFI_IP6].tovpn_sid: 2001:db8:1:1::200 | |
4546 | ||
4547 | ||
8fcedbd2 QY |
4548 | .. _bgp-route-reflector: |
4549 | ||
4550 | Route Reflector | |
4551 | =============== | |
4552 | ||
749afd7d RF |
4553 | BGP routers connected inside the same AS through BGP belong to an internal |
4554 | BGP session, or IBGP. In order to prevent routing table loops, IBGP does not | |
4555 | advertise IBGP-learned routes to other routers in the same session. As such, | |
4556 | IBGP requires a full mesh of all peers. For large networks, this quickly becomes | |
4557 | unscalable. Introducing route reflectors removes the need for the full-mesh. | |
8fcedbd2 | 4558 | |
749afd7d RF |
4559 | When route reflectors are configured, these will reflect the routes announced |
4560 | by the peers configured as clients. A route reflector client is configured | |
4561 | with: | |
8fcedbd2 | 4562 | |
8fcedbd2 QY |
4563 | .. clicmd:: neighbor PEER route-reflector-client |
4564 | ||
c3c5a71f | 4565 | |
749afd7d RF |
4566 | To avoid single points of failure, multiple route reflectors can be configured. |
4567 | ||
4568 | A cluster is a collection of route reflectors and their clients, and is used | |
4569 | by route reflectors to avoid looping. | |
4570 | ||
749afd7d | 4571 | .. clicmd:: bgp cluster-id A.B.C.D |
42fc5d26 | 4572 | |
03750f1e | 4573 | .. clicmd:: bgp no-rib |
8dad2243 DS |
4574 | |
4575 | To set and unset the BGP daemon ``-n`` / ``--no_kernel`` options during runtime | |
4576 | to disable BGP route installation to the RIB (Zebra), the ``[no] bgp no-rib`` | |
4577 | commands can be used; | |
4578 | ||
4579 | Please note that setting the option during runtime will withdraw all routes in | |
4580 | the daemons RIB from Zebra and unsetting it will announce all routes in the | |
4581 | daemons RIB to Zebra. If the option is passed as a command line argument when | |
4582 | starting the daemon and the configuration gets saved, the option will persist | |
4583 | unless removed from the configuration with the negating command prior to the | |
56b91d10 DS |
4584 | configuration write operation. At this point in time non SAFI_UNICAST BGP |
4585 | data is not properly withdrawn from zebra when this command is issued. | |
8dad2243 | 4586 | |
8666265e DS |
4587 | .. clicmd:: bgp allow-martian-nexthop |
4588 | ||
4589 | When a peer receives a martian nexthop as part of the NLRI for a route | |
4590 | permit the nexthop to be used as such, instead of rejecting and resetting | |
4591 | the connection. | |
4592 | ||
03750f1e | 4593 | .. clicmd:: bgp send-extra-data zebra |
9a06c157 | 4594 | |
870791a3 IR |
4595 | This command turns on the ability of BGP to send extra data to zebra. Currently, |
4596 | it's the AS-Path, communities, and the path selection reason. The default | |
4597 | behavior in BGP is not to send this data. If the routes were sent to zebra and | |
4598 | the option is changed, bgpd doesn't reinstall the routes to comply with the new | |
4599 | setting. | |
9a06c157 | 4600 | |
425bd64b PS |
4601 | .. clicmd:: bgp session-dscp (0-63) |
4602 | ||
4603 | This command allows bgp to control, at a global level, the TCP dscp values | |
4604 | in the TCP header. | |
4605 | ||
1cc55938 S |
4606 | .. _bgp-suppress-fib: |
4607 | ||
4608 | Suppressing routes not installed in FIB | |
4609 | ======================================= | |
4610 | ||
4611 | The FRR implementation of BGP advertises prefixes learnt from a peer to other | |
4612 | peers even if the routes do not get installed in the FIB. There can be | |
4613 | scenarios where the hardware tables in some of the routers (along the path from | |
4614 | the source to destination) is full which will result in all routes not getting | |
4615 | installed in the FIB. If these routes are advertised to the downstream routers | |
4616 | then traffic will start flowing and will be dropped at the intermediate router. | |
4617 | ||
4618 | The solution is to provide a configurable option to check for the FIB install | |
4619 | status of the prefixes and advertise to peers if the prefixes are successfully | |
4620 | installed in the FIB. The advertisement of the prefixes are suppressed if it is | |
4621 | not installed in FIB. | |
4622 | ||
4623 | The following conditions apply will apply when checking for route installation | |
4624 | status in FIB: | |
0ea5223c | 4625 | |
1cc55938 S |
4626 | 1. The advertisement or suppression of routes based on FIB install status |
4627 | applies only for newly learnt routes from peer (routes which are not in | |
4628 | BGP local RIB). | |
4629 | 2. If the route received from peer already exists in BGP local RIB and route | |
4630 | attributes have changed (best path changed), the old path is deleted and | |
4631 | new path is installed in FIB. The FIB install status will not have any | |
4632 | effect. Therefore only when the route is received first time the checks | |
4633 | apply. | |
4634 | 3. The feature will not apply for routes learnt through other means like | |
4635 | redistribution to bgp from other protocols. This is applicable only to | |
4636 | peer learnt routes. | |
4637 | 4. If a route is installed in FIB and then gets deleted from the dataplane, | |
4638 | then routes will not be withdrawn from peers. This will be considered as | |
4639 | dataplane issue. | |
4640 | 5. The feature will slightly increase the time required to advertise the routes | |
4641 | to peers since the route install status needs to be received from the FIB | |
4642 | 6. If routes are received by the peer before the configuration is applied, then | |
4643 | the bgp sessions need to be reset for the configuration to take effect. | |
4644 | 7. If the route which is already installed in dataplane is removed for some | |
4645 | reason, sending withdraw message to peers is not currently supported. | |
4646 | ||
03750f1e | 4647 | .. clicmd:: bgp suppress-fib-pending |
8dad2243 | 4648 | |
4f4ba68c DS |
4649 | This command is applicable at the global level and at an individual |
4650 | bgp level. If applied at the global level all bgp instances will | |
4651 | wait for fib installation before announcing routes and there is no | |
4652 | way to turn it off for a particular bgp vrf. | |
4653 | ||
0efdf0fe | 4654 | .. _routing-policy: |
42fc5d26 | 4655 | |
8fcedbd2 QY |
4656 | Routing Policy |
4657 | ============== | |
42fc5d26 | 4658 | |
4da7fda3 | 4659 | You can set different routing policy for a peer. For example, you can set |
9eb95b3b QY |
4660 | different filter for a peer. |
4661 | ||
4662 | .. code-block:: frr | |
c1a54c05 | 4663 | |
c1a54c05 QY |
4664 | ! |
4665 | router bgp 1 view 1 | |
4666 | neighbor 10.0.0.1 remote-as 2 | |
4667 | address-family ipv4 unicast | |
4668 | neighbor 10.0.0.1 distribute-list 1 in | |
4669 | exit-address-family | |
4670 | ! | |
4671 | router bgp 1 view 2 | |
4672 | neighbor 10.0.0.1 remote-as 2 | |
4673 | address-family ipv4 unicast | |
4674 | neighbor 10.0.0.1 distribute-list 2 in | |
4675 | exit-address-family | |
c3c5a71f | 4676 | |
4da7fda3 QY |
4677 | This means BGP update from a peer 10.0.0.1 goes to both BGP view 1 and view 2. |
4678 | When the update is inserted into view 1, distribute-list 1 is applied. On the | |
4679 | other hand, when the update is inserted into view 2, distribute-list 2 is | |
4680 | applied. | |
42fc5d26 | 4681 | |
42fc5d26 | 4682 | |
0efdf0fe | 4683 | .. _bgp-regular-expressions: |
42fc5d26 QY |
4684 | |
4685 | BGP Regular Expressions | |
4686 | ======================= | |
4687 | ||
8fcedbd2 QY |
4688 | BGP regular expressions are based on :t:`POSIX 1003.2` regular expressions. The |
4689 | following description is just a quick subset of the POSIX regular expressions. | |
42fc5d26 QY |
4690 | |
4691 | ||
8fcedbd2 | 4692 | .\* |
c1a54c05 | 4693 | Matches any single character. |
42fc5d26 | 4694 | |
8fcedbd2 | 4695 | \* |
c1a54c05 | 4696 | Matches 0 or more occurrences of pattern. |
42fc5d26 | 4697 | |
8fcedbd2 | 4698 | \+ |
c1a54c05 | 4699 | Matches 1 or more occurrences of pattern. |
42fc5d26 QY |
4700 | |
4701 | ? | |
c1a54c05 | 4702 | Match 0 or 1 occurrences of pattern. |
42fc5d26 QY |
4703 | |
4704 | ^ | |
c1a54c05 | 4705 | Matches the beginning of the line. |
42fc5d26 QY |
4706 | |
4707 | $ | |
c1a54c05 | 4708 | Matches the end of the line. |
42fc5d26 QY |
4709 | |
4710 | _ | |
8fcedbd2 QY |
4711 | The ``_`` character has special meanings in BGP regular expressions. It |
4712 | matches to space and comma , and AS set delimiter ``{`` and ``}`` and AS | |
4713 | confederation delimiter ``(`` and ``)``. And it also matches to the | |
4714 | beginning of the line and the end of the line. So ``_`` can be used for AS | |
4715 | value boundaries match. This character technically evaluates to | |
4716 | ``(^|[,{}()]|$)``. | |
42fc5d26 | 4717 | |
42fc5d26 | 4718 | |
c1a54c05 | 4719 | .. _bgp-configuration-examples: |
42fc5d26 | 4720 | |
8fcedbd2 QY |
4721 | Miscellaneous Configuration Examples |
4722 | ==================================== | |
42fc5d26 | 4723 | |
9eb95b3b QY |
4724 | Example of a session to an upstream, advertising only one prefix to it. |
4725 | ||
4726 | .. code-block:: frr | |
42fc5d26 | 4727 | |
c1a54c05 QY |
4728 | router bgp 64512 |
4729 | bgp router-id 10.236.87.1 | |
4730 | neighbor upstream peer-group | |
4731 | neighbor upstream remote-as 64515 | |
4732 | neighbor upstream capability dynamic | |
4733 | neighbor 10.1.1.1 peer-group upstream | |
4734 | neighbor 10.1.1.1 description ACME ISP | |
c3c5a71f | 4735 | |
c1a54c05 QY |
4736 | address-family ipv4 unicast |
4737 | network 10.236.87.0/24 | |
4738 | neighbor upstream prefix-list pl-allowed-adv out | |
4739 | exit-address-family | |
4740 | ! | |
4741 | ip prefix-list pl-allowed-adv seq 5 permit 82.195.133.0/25 | |
4742 | ip prefix-list pl-allowed-adv seq 10 deny any | |
42fc5d26 | 4743 | |
aa9eafa4 QY |
4744 | A more complex example including upstream, peer and customer sessions |
4745 | advertising global prefixes and NO_EXPORT prefixes and providing actions for | |
4746 | customer routes based on community values. Extensive use is made of route-maps | |
4747 | and the 'call' feature to support selective advertising of prefixes. This | |
4748 | example is intended as guidance only, it has NOT been tested and almost | |
4749 | certainly contains silly mistakes, if not serious flaws. | |
42fc5d26 | 4750 | |
9eb95b3b | 4751 | .. code-block:: frr |
42fc5d26 | 4752 | |
c1a54c05 QY |
4753 | router bgp 64512 |
4754 | bgp router-id 10.236.87.1 | |
4755 | neighbor upstream capability dynamic | |
4756 | neighbor cust capability dynamic | |
4757 | neighbor peer capability dynamic | |
4758 | neighbor 10.1.1.1 remote-as 64515 | |
4759 | neighbor 10.1.1.1 peer-group upstream | |
4760 | neighbor 10.2.1.1 remote-as 64516 | |
4761 | neighbor 10.2.1.1 peer-group upstream | |
4762 | neighbor 10.3.1.1 remote-as 64517 | |
4763 | neighbor 10.3.1.1 peer-group cust-default | |
4764 | neighbor 10.3.1.1 description customer1 | |
4765 | neighbor 10.4.1.1 remote-as 64518 | |
4766 | neighbor 10.4.1.1 peer-group cust | |
4767 | neighbor 10.4.1.1 description customer2 | |
4768 | neighbor 10.5.1.1 remote-as 64519 | |
4769 | neighbor 10.5.1.1 peer-group peer | |
4770 | neighbor 10.5.1.1 description peer AS 1 | |
4771 | neighbor 10.6.1.1 remote-as 64520 | |
4772 | neighbor 10.6.1.1 peer-group peer | |
4773 | neighbor 10.6.1.1 description peer AS 2 | |
4774 | ||
4775 | address-family ipv4 unicast | |
4776 | network 10.123.456.0/24 | |
4777 | network 10.123.456.128/25 route-map rm-no-export | |
4778 | neighbor upstream route-map rm-upstream-out out | |
4779 | neighbor cust route-map rm-cust-in in | |
4780 | neighbor cust route-map rm-cust-out out | |
4781 | neighbor cust send-community both | |
4782 | neighbor peer route-map rm-peer-in in | |
4783 | neighbor peer route-map rm-peer-out out | |
4784 | neighbor peer send-community both | |
4785 | neighbor 10.3.1.1 prefix-list pl-cust1-network in | |
4786 | neighbor 10.4.1.1 prefix-list pl-cust2-network in | |
4787 | neighbor 10.5.1.1 prefix-list pl-peer1-network in | |
4788 | neighbor 10.6.1.1 prefix-list pl-peer2-network in | |
4789 | exit-address-family | |
4790 | ! | |
4791 | ip prefix-list pl-default permit 0.0.0.0/0 | |
4792 | ! | |
4793 | ip prefix-list pl-upstream-peers permit 10.1.1.1/32 | |
4794 | ip prefix-list pl-upstream-peers permit 10.2.1.1/32 | |
4795 | ! | |
4796 | ip prefix-list pl-cust1-network permit 10.3.1.0/24 | |
4797 | ip prefix-list pl-cust1-network permit 10.3.2.0/24 | |
4798 | ! | |
4799 | ip prefix-list pl-cust2-network permit 10.4.1.0/24 | |
4800 | ! | |
4801 | ip prefix-list pl-peer1-network permit 10.5.1.0/24 | |
4802 | ip prefix-list pl-peer1-network permit 10.5.2.0/24 | |
4803 | ip prefix-list pl-peer1-network permit 192.168.0.0/24 | |
4804 | ! | |
4805 | ip prefix-list pl-peer2-network permit 10.6.1.0/24 | |
4806 | ip prefix-list pl-peer2-network permit 10.6.2.0/24 | |
4807 | ip prefix-list pl-peer2-network permit 192.168.1.0/24 | |
4808 | ip prefix-list pl-peer2-network permit 192.168.2.0/24 | |
4809 | ip prefix-list pl-peer2-network permit 172.16.1/24 | |
4810 | ! | |
e6e62ee5 CS |
4811 | bgp as-path access-list seq 5 asp-own-as permit ^$ |
4812 | bgp as-path access-list seq 10 asp-own-as permit _64512_ | |
c1a54c05 QY |
4813 | ! |
4814 | ! ################################################################# | |
4815 | ! Match communities we provide actions for, on routes receives from | |
4816 | ! customers. Communities values of <our-ASN>:X, with X, have actions: | |
4817 | ! | |
4818 | ! 100 - blackhole the prefix | |
4819 | ! 200 - set no_export | |
4820 | ! 300 - advertise only to other customers | |
4821 | ! 400 - advertise only to upstreams | |
4822 | ! 500 - set no_export when advertising to upstreams | |
4823 | ! 2X00 - set local_preference to X00 | |
4824 | ! | |
4825 | ! blackhole the prefix of the route | |
a64e0ee5 | 4826 | bgp community-list standard cm-blackhole permit 64512:100 |
c1a54c05 QY |
4827 | ! |
4828 | ! set no-export community before advertising | |
a64e0ee5 | 4829 | bgp community-list standard cm-set-no-export permit 64512:200 |
c1a54c05 QY |
4830 | ! |
4831 | ! advertise only to other customers | |
a64e0ee5 | 4832 | bgp community-list standard cm-cust-only permit 64512:300 |
c1a54c05 QY |
4833 | ! |
4834 | ! advertise only to upstreams | |
a64e0ee5 | 4835 | bgp community-list standard cm-upstream-only permit 64512:400 |
c1a54c05 QY |
4836 | ! |
4837 | ! advertise to upstreams with no-export | |
a64e0ee5 | 4838 | bgp community-list standard cm-upstream-noexport permit 64512:500 |
c1a54c05 QY |
4839 | ! |
4840 | ! set local-pref to least significant 3 digits of the community | |
a64e0ee5 DA |
4841 | bgp community-list standard cm-prefmod-100 permit 64512:2100 |
4842 | bgp community-list standard cm-prefmod-200 permit 64512:2200 | |
4843 | bgp community-list standard cm-prefmod-300 permit 64512:2300 | |
4844 | bgp community-list standard cm-prefmod-400 permit 64512:2400 | |
4845 | bgp community-list expanded cme-prefmod-range permit 64512:2... | |
c1a54c05 QY |
4846 | ! |
4847 | ! Informational communities | |
4848 | ! | |
4849 | ! 3000 - learned from upstream | |
4850 | ! 3100 - learned from customer | |
4851 | ! 3200 - learned from peer | |
4852 | ! | |
a64e0ee5 DA |
4853 | bgp community-list standard cm-learnt-upstream permit 64512:3000 |
4854 | bgp community-list standard cm-learnt-cust permit 64512:3100 | |
4855 | bgp community-list standard cm-learnt-peer permit 64512:3200 | |
c1a54c05 QY |
4856 | ! |
4857 | ! ################################################################### | |
4858 | ! Utility route-maps | |
4859 | ! | |
4860 | ! These utility route-maps generally should not used to permit/deny | |
4861 | ! routes, i.e. they do not have meaning as filters, and hence probably | |
4862 | ! should be used with 'on-match next'. These all finish with an empty | |
4863 | ! permit entry so as not interfere with processing in the caller. | |
4864 | ! | |
4865 | route-map rm-no-export permit 10 | |
4866 | set community additive no-export | |
4867 | route-map rm-no-export permit 20 | |
4868 | ! | |
4869 | route-map rm-blackhole permit 10 | |
f6aa36f5 | 4870 | description blackhole, up-pref and ensure it cannot escape this AS |
c1a54c05 QY |
4871 | set ip next-hop 127.0.0.1 |
4872 | set local-preference 10 | |
4873 | set community additive no-export | |
4874 | route-map rm-blackhole permit 20 | |
4875 | ! | |
4876 | ! Set local-pref as requested | |
4877 | route-map rm-prefmod permit 10 | |
4878 | match community cm-prefmod-100 | |
4879 | set local-preference 100 | |
4880 | route-map rm-prefmod permit 20 | |
4881 | match community cm-prefmod-200 | |
4882 | set local-preference 200 | |
4883 | route-map rm-prefmod permit 30 | |
4884 | match community cm-prefmod-300 | |
4885 | set local-preference 300 | |
4886 | route-map rm-prefmod permit 40 | |
4887 | match community cm-prefmod-400 | |
4888 | set local-preference 400 | |
4889 | route-map rm-prefmod permit 50 | |
4890 | ! | |
4891 | ! Community actions to take on receipt of route. | |
4892 | route-map rm-community-in permit 10 | |
4893 | description check for blackholing, no point continuing if it matches. | |
4894 | match community cm-blackhole | |
4895 | call rm-blackhole | |
4896 | route-map rm-community-in permit 20 | |
4897 | match community cm-set-no-export | |
4898 | call rm-no-export | |
4899 | on-match next | |
4900 | route-map rm-community-in permit 30 | |
4901 | match community cme-prefmod-range | |
4902 | call rm-prefmod | |
4903 | route-map rm-community-in permit 40 | |
4904 | ! | |
4905 | ! ##################################################################### | |
4906 | ! Community actions to take when advertising a route. | |
4907 | ! These are filtering route-maps, | |
4908 | ! | |
4909 | ! Deny customer routes to upstream with cust-only set. | |
4910 | route-map rm-community-filt-to-upstream deny 10 | |
4911 | match community cm-learnt-cust | |
4912 | match community cm-cust-only | |
4913 | route-map rm-community-filt-to-upstream permit 20 | |
4914 | ! | |
4915 | ! Deny customer routes to other customers with upstream-only set. | |
4916 | route-map rm-community-filt-to-cust deny 10 | |
4917 | match community cm-learnt-cust | |
4918 | match community cm-upstream-only | |
4919 | route-map rm-community-filt-to-cust permit 20 | |
4920 | ! | |
4921 | ! ################################################################### | |
4922 | ! The top-level route-maps applied to sessions. Further entries could | |
4923 | ! be added obviously.. | |
4924 | ! | |
4925 | ! Customers | |
4926 | route-map rm-cust-in permit 10 | |
4927 | call rm-community-in | |
4928 | on-match next | |
4929 | route-map rm-cust-in permit 20 | |
4930 | set community additive 64512:3100 | |
4931 | route-map rm-cust-in permit 30 | |
4932 | ! | |
4933 | route-map rm-cust-out permit 10 | |
4934 | call rm-community-filt-to-cust | |
4935 | on-match next | |
4936 | route-map rm-cust-out permit 20 | |
4937 | ! | |
4938 | ! Upstream transit ASes | |
4939 | route-map rm-upstream-out permit 10 | |
4940 | description filter customer prefixes which are marked cust-only | |
4941 | call rm-community-filt-to-upstream | |
4942 | on-match next | |
4943 | route-map rm-upstream-out permit 20 | |
4944 | description only customer routes are provided to upstreams/peers | |
4945 | match community cm-learnt-cust | |
4946 | ! | |
4947 | ! Peer ASes | |
4948 | ! outbound policy is same as for upstream | |
4949 | route-map rm-peer-out permit 10 | |
4950 | call rm-upstream-out | |
4951 | ! | |
4952 | route-map rm-peer-in permit 10 | |
4953 | set community additive 64512:3200 | |
c3c5a71f | 4954 | |
8fcedbd2 QY |
4955 | |
4956 | Example of how to set up a 6-Bone connection. | |
4957 | ||
4958 | .. code-block:: frr | |
4959 | ||
4960 | ! bgpd configuration | |
4961 | ! ================== | |
4962 | ! | |
4963 | ! MP-BGP configuration | |
4964 | ! | |
4965 | router bgp 7675 | |
4966 | bgp router-id 10.0.0.1 | |
4967 | neighbor 3ffe:1cfa:0:2:2a0:c9ff:fe9e:f56 remote-as `as-number` | |
4968 | ! | |
4969 | address-family ipv6 | |
4970 | network 3ffe:506::/32 | |
4971 | neighbor 3ffe:1cfa:0:2:2a0:c9ff:fe9e:f56 activate | |
4972 | neighbor 3ffe:1cfa:0:2:2a0:c9ff:fe9e:f56 route-map set-nexthop out | |
4973 | neighbor 3ffe:1cfa:0:2:2c0:4fff:fe68:a231 remote-as `as-number` | |
4974 | neighbor 3ffe:1cfa:0:2:2c0:4fff:fe68:a231 route-map set-nexthop out | |
4975 | exit-address-family | |
4976 | ! | |
4977 | ipv6 access-list all permit any | |
4978 | ! | |
4979 | ! Set output nexthop address. | |
4980 | ! | |
4981 | route-map set-nexthop permit 10 | |
4982 | match ipv6 address all | |
4983 | set ipv6 nexthop global 3ffe:1cfa:0:2:2c0:4fff:fe68:a225 | |
4984 | set ipv6 nexthop local fe80::2c0:4fff:fe68:a225 | |
4985 | ! | |
4986 | log file bgpd.log | |
4987 | ! | |
4988 | ||
4ab46701 AR |
4989 | .. _bgp-tcp-mss: |
4990 | ||
4991 | BGP tcp-mss support | |
4992 | =================== | |
4993 | TCP provides a mechanism for the user to specify the max segment size. | |
4994 | setsockopt API is used to set the max segment size for TCP session. We | |
4995 | can configure this as part of BGP neighbor configuration. | |
4996 | ||
4997 | This document explains how to avoid ICMP vulnerability issues by limiting | |
4998 | TCP max segment size when you are using MTU discovery. Using MTU discovery | |
4999 | on TCP paths is one method of avoiding BGP packet fragmentation. | |
5000 | ||
5001 | TCP negotiates a maximum segment size (MSS) value during session connection | |
5002 | establishment between two peers. The MSS value negotiated is primarily based | |
073b7664 DA |
5003 | on the maximum transmission unit (MTU) of the interfaces to which the |
5004 | communicating peers are directly connected. However, due to variations in | |
5005 | link MTU on the path taken by the TCP packets, some packets in the network | |
4ab46701 | 5006 | that are well within the MSS value might be fragmented when the packet size |
073b7664 | 5007 | exceeds the link's MTU. |
4ab46701 AR |
5008 | |
5009 | This feature is supported with TCP over IPv4 and TCP over IPv6. | |
5010 | ||
5011 | CLI Configuration: | |
5012 | ------------------ | |
5013 | Below configuration can be done in router bgp mode and allows the user to | |
5014 | configure the tcp-mss value per neighbor. The configuration gets applied | |
5015 | only after hard reset is performed on that neighbor. If we configure tcp-mss | |
5016 | on both the neighbors then both neighbors need to be reset. | |
5017 | ||
5018 | The configuration takes effect based on below rules, so there is a configured | |
5019 | tcp-mss and a synced tcp-mss value per TCP session. | |
5020 | ||
5021 | By default if the configuration is not done then the TCP max segment size is | |
5022 | set to the Maximum Transmission unit (MTU) – (IP/IP6 header size + TCP header | |
5023 | size + ethernet header). For IPv4 its MTU – (20 bytes IP header + 20 bytes TCP | |
5024 | header + 12 bytes ethernet header) and for IPv6 its MTU – (40 bytes IPv6 header | |
5025 | + 20 bytes TCP header + 12 bytes ethernet header). | |
5026 | ||
073b7664 | 5027 | If the config is done then it reduces 12-14 bytes for the ether header and |
4ab46701 AR |
5028 | uses it after synchronizing in TCP handshake. |
5029 | ||
5030 | .. clicmd:: neighbor <A.B.C.D|X:X::X:X|WORD> tcp-mss (1-65535) | |
5031 | ||
5032 | When tcp-mss is configured kernel reduces 12-14 bytes for ethernet header. | |
5033 | E.g. if tcp-mss is configured as 150 the synced value will be 138. | |
5034 | ||
5035 | Note: configured and synced value is different since TCP module will reduce | |
5036 | 12 bytes for ethernet header. | |
5037 | ||
5038 | Running config: | |
5039 | --------------- | |
5040 | ||
5041 | .. code-block:: frr | |
5042 | ||
073b7664 | 5043 | frr# show running-config |
4ab46701 AR |
5044 | Building configuration... |
5045 | ||
5046 | Current configuration: | |
5047 | ! | |
5048 | router bgp 100 | |
5049 | bgp router-id 192.0.2.1 | |
5050 | neighbor 198.51.100.2 remote-as 100 | |
5051 | neighbor 198.51.100.2 tcp-mss 150 => new entry | |
5052 | neighbor 2001:DB8::2 remote-as 100 | |
5053 | neighbor 2001:DB8::2 tcp-mss 400 => new entry | |
5054 | ||
5055 | Show command: | |
5056 | ------------- | |
5057 | ||
5058 | .. code-block:: frr | |
5059 | ||
073b7664 | 5060 | frr# show bgp neighbors 198.51.100.2 |
4ab46701 AR |
5061 | BGP neighbor is 198.51.100.2, remote AS 100, local AS 100, internal link |
5062 | Hostname: frr | |
5063 | BGP version 4, remote router ID 192.0.2.2, local router ID 192.0.2.1 | |
5064 | BGP state = Established, up for 02:15:28 | |
5065 | Last read 00:00:28, Last write 00:00:28 | |
5066 | Hold time is 180, keepalive interval is 60 seconds | |
5067 | Configured tcp-mss is 150, synced tcp-mss is 138 => new display | |
5068 | ||
5069 | .. code-block:: frr | |
5070 | ||
073b7664 | 5071 | frr# show bgp neighbors 2001:DB8::2 |
4ab46701 AR |
5072 | BGP neighbor is 2001:DB8::2, remote AS 100, local AS 100, internal link |
5073 | Hostname: frr | |
5074 | BGP version 4, remote router ID 192.0.2.2, local router ID 192.0.2.1 | |
5075 | BGP state = Established, up for 02:16:34 | |
5076 | Last read 00:00:34, Last write 00:00:34 | |
5077 | Hold time is 180, keepalive interval is 60 seconds | |
5078 | Configured tcp-mss is 400, synced tcp-mss is 388 => new display | |
5079 | ||
5080 | Show command json output: | |
5081 | ------------------------- | |
5082 | ||
5083 | .. code-block:: frr | |
5084 | ||
073b7664 | 5085 | frr# show bgp neighbors 2001:DB8::2 json |
4ab46701 AR |
5086 | { |
5087 | "2001:DB8::2":{ | |
5088 | "remoteAs":100, | |
5089 | "localAs":100, | |
5090 | "nbrInternalLink":true, | |
5091 | "hostname":"frr", | |
5092 | "bgpVersion":4, | |
5093 | "remoteRouterId":"192.0.2.2", | |
5094 | "localRouterId":"192.0.2.1", | |
5095 | "bgpState":"Established", | |
5096 | "bgpTimerUpMsec":8349000, | |
5097 | "bgpTimerUpString":"02:19:09", | |
5098 | "bgpTimerUpEstablishedEpoch":1613054251, | |
5099 | "bgpTimerLastRead":9000, | |
5100 | "bgpTimerLastWrite":9000, | |
5101 | "bgpInUpdateElapsedTimeMsecs":8347000, | |
5102 | "bgpTimerHoldTimeMsecs":180000, | |
5103 | "bgpTimerKeepAliveIntervalMsecs":60000, | |
5104 | "bgpTcpMssConfigured":400, => new entry | |
5105 | "bgpTcpMssSynced":388, => new entry | |
5106 | ||
5107 | .. code-block:: frr | |
5108 | ||
073b7664 | 5109 | frr# show bgp neighbors 198.51.100.2 json |
4ab46701 AR |
5110 | { |
5111 | "198.51.100.2":{ | |
5112 | "remoteAs":100, | |
5113 | "localAs":100, | |
5114 | "nbrInternalLink":true, | |
5115 | "hostname":"frr", | |
5116 | "bgpVersion":4, | |
5117 | "remoteRouterId":"192.0.2.2", | |
5118 | "localRouterId":"192.0.2.1", | |
5119 | "bgpState":"Established", | |
5120 | "bgpTimerUpMsec":8370000, | |
5121 | "bgpTimerUpString":"02:19:30", | |
5122 | "bgpTimerUpEstablishedEpoch":1613054251, | |
5123 | "bgpTimerLastRead":30000, | |
5124 | "bgpTimerLastWrite":30000, | |
5125 | "bgpInUpdateElapsedTimeMsecs":8368000, | |
5126 | "bgpTimerHoldTimeMsecs":180000, | |
5127 | "bgpTimerKeepAliveIntervalMsecs":60000, | |
5128 | "bgpTcpMssConfigured":150, => new entry | |
5129 | "bgpTcpMssSynced":138, => new entry | |
8fcedbd2 | 5130 | |
9e146a81 | 5131 | .. include:: routeserver.rst |
f3817860 QY |
5132 | |
5133 | .. include:: rpki.rst | |
c1a54c05 | 5134 | |
ed647ed2 | 5135 | .. include:: wecmp_linkbw.rst |
5136 | ||
00458d01 PG |
5137 | .. include:: flowspec.rst |
5138 | ||
d1e7591e | 5139 | .. [#med-transitivity-rant] For some set of objects to have an order, there *must* be some binary ordering relation that is defined for *every* combination of those objects, and that relation *must* be transitive. I.e.:, if the relation operator is <, and if a < b and b < c then that relation must carry over and it *must* be that a < c for the objects to have an order. The ordering relation may allow for equality, i.e. a < b and b < a may both be true and imply that a and b are equal in the order and not distinguished by it, in which case the set has a partial order. Otherwise, if there is an order, all the objects have a distinct place in the order and the set has a total order) |
c1a54c05 QY |
5140 | .. [bgp-route-osci-cond] McPherson, D. and Gill, V. and Walton, D., "Border Gateway Protocol (BGP) Persistent Route Oscillation Condition", IETF RFC3345 |
5141 | .. [stable-flexible-ibgp] Flavel, A. and M. Roughan, "Stable and flexible iBGP", ACM SIGCOMM 2009 | |
5142 | .. [ibgp-correctness] Griffin, T. and G. Wilfong, "On the correctness of IBGP configuration", ACM SIGCOMM 2002 | |
5874235f PG |
5143 | |
5144 | .. _bgp-fast-convergence: | |
5145 | ||
5146 | BGP fast-convergence support | |
5147 | ============================ | |
5148 | Whenever BGP peer address becomes unreachable we must bring down the BGP | |
7cb0494d DA |
5149 | session immediately. Currently only single-hop EBGP sessions are brought |
5150 | down immediately.IBGP and multi-hop EBGP sessions wait for hold-timer | |
5874235f PG |
5151 | expiry to bring down the sessions. |
5152 | ||
5153 | This new configuration option helps user to teardown BGP sessions immediately | |
5154 | whenever peer becomes unreachable. | |
5155 | ||
5156 | .. clicmd:: bgp fast-convergence | |
5157 | ||
5158 | This configuration is available at the bgp level. When enabled, configuration | |
5159 | is applied to all the neighbors configured in that bgp instance. | |
5160 | ||
5161 | .. code-block:: frr | |
5162 | ||
5163 | router bgp 64496 | |
5164 | neighbor 10.0.0.2 remote-as 64496 | |
5165 | neighbor fd00::2 remote-as 64496 | |
5166 | bgp fast-convergence | |
5167 | ! | |
5168 | address-family ipv4 unicast | |
5169 | redistribute static | |
5170 | exit-address-family | |
5171 | ! | |
5172 | address-family ipv6 unicast | |
5173 | neighbor fd00::2 activate | |
5174 | exit-address-family |