doc/user/isisd.rst

   1 .. _isis:
   2
   3 ****
   4 ISIS
   5 ****
   6
   7 :abbr:`ISIS (Intermediate System to Intermediate System)` is a routing protocol
   8 which is described in :t:`ISO10589`, :rfc:`1195`, :rfc:`5308`. ISIS is an
   9 :abbr:`IGP (Interior Gateway Protocol)`. Compared with :abbr:`RIP`,
  10 :abbr:`ISIS` can provide scalable network support and faster convergence times
  11 like :abbr:`OSPF`. ISIS is widely used in large networks such as :abbr:`ISP
  12 (Internet Service Provider)` and carrier backbone networks.
  13
  14 .. _configuring-isisd:
  15
  16 Configuring isisd
  17 =================
  18
  19 There are no *isisd* specific options. Common options can be specified
  20 (:ref:`common-invocation-options`) to *isisd*. *isisd* needs to acquire
  21 interface information from *zebra* in order to function. Therefore *zebra* must
  22 be running before invoking *isisd*. Also, if *zebra* is restarted then *isisd*
  23 must be too.
  24
  25 Like other daemons, *isisd* configuration is done in :abbr:`ISIS` specific
  26 configuration file :file:`isisd.conf`.
  27
  28 .. _isis-router:
  29
  30 ISIS router
  31 ===========
  32
  33 To start the ISIS process you have to specify the ISIS router. As of this
  34 writing, *isisd* does not support multiple ISIS processes.
  35
  36 .. clicmd:: router isis WORD [vrf NAME]
  37
  38    Enable or disable the ISIS process by specifying the ISIS domain with
  39    'WORD'.  *isisd* does not yet support multiple ISIS processes but you must
  40    specify the name of ISIS process. The ISIS process name 'WORD' is then used
  41    for interface (see command :clicmd:`ip router isis WORD`).
  42
  43 .. clicmd:: net XX.XXXX. ... .XXX.XX
  44
  45    Set/Unset network entity title (NET) provided in ISO format.
  46
  47 .. clicmd:: hostname dynamic
  48
  49    Enable support for dynamic hostname.
  50
  51 .. clicmd:: area-password [clear | md5] <password>
  52
  53 .. clicmd:: domain-password [clear | md5] <password>
  54
  55    Configure the authentication password for an area, respectively a domain, as
  56    clear text or md5 one.
  57
  58 .. clicmd:: attached-bit [receive ignore | send]
  59
  60    Set attached bit for inter-area traffic:
  61
  62    - receive
  63      If LSP received with attached bit set, create default route to neighbor
  64    - send
  65      If L1|L2 router, set attached bit in LSP sent to L1 router
  66
  67 .. clicmd:: log-adjacency-changes
  68
  69    Log changes in adjacency state.
  70
  71 .. clicmd:: metric-style [narrow | transition | wide]
  72
  73    Set old-style (ISO 10589) or new-style packet formats:
  74
  75    - narrow
  76      Use old style of TLVs with narrow metric
  77    - transition
  78      Send and accept both styles of TLVs during transition
  79    - wide
  80      Use new style of TLVs to carry wider metric. FRR uses this as a default value
  81
  82 .. clicmd:: set-overload-bit
  83
  84    Set overload bit to avoid any transit traffic.
  85
  86 .. clicmd:: set-overload-bit on-startup (0-86400)
  87
  88    Set overload bit on startup for the specified duration, in seconds. Reference: :rfc:`3277`
  89
  90 .. clicmd:: purge-originator
  91
  92    Enable or disable :rfc:`6232` purge originator identification.
  93
  94 .. clicmd:: lsp-mtu (128-4352)
  95
  96    Configure the maximum size of generated LSPs, in bytes.
  97
  98
  99 .. _isis-timer:
 100
 101 ISIS Timer
 102 ==========
 103
 104 .. clicmd:: lsp-gen-interval [level-1 | level-2] (1-120)
 105
 106    Set minimum interval in seconds between regenerating same LSP,
 107    globally, for an area (level-1) or a domain (level-2).
 108
 109 .. clicmd:: lsp-refresh-interval [level-1 | level-2] (1-65235)
 110
 111    Set LSP refresh interval in seconds, globally, for an area (level-1) or a
 112    domain (level-2).
 113
 114 .. clicmd:: max-lsp-lifetime [level-1 | level-2] (360-65535)
 115
 116    Set LSP maximum LSP lifetime in seconds, globally, for an area (level-1) or
 117    a domain (level-2).
 118
 119 .. clicmd:: spf-interval [level-1 | level-2] (1-120)
 120
 121    Set minimum interval between consecutive SPF calculations in seconds.
 122
 123 .. _isis-fast-reroute:
 124
 125 ISIS Fast-Reroute
 126 =================
 127
 128 Unless stated otherwise, commands in this section apply to all LFA
 129 flavors (local LFA, Remote LFA and TI-LFA).
 130
 131 .. clicmd:: spf prefix-priority [critical | high | medium] WORD
 132
 133    Assign a priority to the prefixes that match the specified access-list.
 134
 135    By default loopback prefixes have medium priority and non-loopback prefixes
 136    have low priority.
 137
 138 .. clicmd:: fast-reroute priority-limit [critical | high | medium] [level-1 | level-2]
 139
 140    Limit LFA backup computation up to the specified prefix priority.
 141
 142 .. clicmd:: fast-reroute lfa tiebreaker [downstream | lowest-backup-metric | node-protecting] index (1-255) [level-1 | level-2]
 143
 144    Configure a tie-breaker for multiple local LFA backups. Lower indexes are
 145    processed first.
 146
 147 .. clicmd:: fast-reroute load-sharing disable [level-1 | level-2]
 148
 149    Disable load sharing across multiple LFA backups.
 150
 151 .. clicmd:: fast-reroute remote-lfa prefix-list [WORD] [level-1 | level-2]
 152
 153    Configure a prefix-list to select eligible PQ nodes for remote LFA
 154    backups (valid for all protected interfaces).
 155
 156 .. _isis-region:
 157
 158 ISIS region
 159 ===========
 160
 161 .. clicmd:: is-type [level-1 | level-1-2 | level-2-only]
 162
 163    Define the ISIS router behavior:
 164
 165    - level-1
 166      Act as a station router only
 167    - level-1-2
 168      Act as both a station router and an area router
 169    - level-2-only
 170      Act as an area router only
 171
 172 .. _isis-interface:
 173
 174 ISIS interface
 175 ==============
 176
 177 .. _ip-router-isis-word:
 178
 179 .. clicmd:: <ip|ipv6> router isis WORD
 180
 181    Activate ISIS adjacency on this interface. Note that the name of ISIS
 182    instance must be the same as the one used to configure the ISIS process (see
 183    command :clicmd:`router isis WORD`). To enable IPv4, issue ``ip router isis
 184    WORD``; to enable IPv6, issue ``ipv6 router isis WORD``.
 185
 186 .. clicmd:: isis circuit-type [level-1 | level-1-2 | level-2]
 187
 188    Configure circuit type for interface:
 189
 190    - level-1
 191      Level-1 only adjacencies are formed
 192    - level-1-2
 193      Level-1-2 adjacencies are formed
 194    - level-2-only
 195      Level-2 only adjacencies are formed
 196
 197 .. clicmd:: isis csnp-interval (1-600) [level-1 | level-2]
 198
 199    Set CSNP interval in seconds globally, for an area (level-1) or a domain
 200    (level-2).
 201
 202 .. clicmd:: isis hello padding
 203
 204    Add padding to IS-IS hello packets.
 205
 206 .. clicmd:: isis hello-interval (1-600) [level-1 | level-2]
 207
 208    Set Hello interval in seconds globally, for an area (level-1) or a domain
 209    (level-2).
 210
 211 .. clicmd:: isis hello-multiplier (2-100) [level-1 | level-2]
 212
 213    Set multiplier for Hello holding time globally, for an area (level-1) or a
 214    domain (level-2).
 215
 216 .. clicmd:: isis metric [(0-255) | (0-16777215)] [level-1 | level-2]
 217
 218    Set default metric value globally, for an area (level-1) or a domain
 219    (level-2).  Max value depend if metric support narrow or wide value (see
 220    command :clicmd:`metric-style [narrow | transition | wide]`).
 221
 222 .. clicmd:: isis network point-to-point
 223
 224    Set network type to 'Point-to-Point' (broadcast by default).
 225
 226 .. clicmd:: isis passive
 227
 228    Configure the passive mode for this interface.
 229
 230 .. clicmd:: isis password [clear | md5] <password>
 231
 232    Configure the authentication password (clear or encoded text) for the
 233    interface.
 234
 235 .. clicmd:: isis priority (0-127) [level-1 | level-2]
 236
 237    Set priority for Designated Router election, globally, for the area
 238    (level-1) or the domain (level-2).
 239
 240 .. clicmd:: isis psnp-interval (1-120) [level-1 | level-2]
 241
 242    Set PSNP interval in seconds globally, for an area (level-1) or a domain
 243    (level-2).
 244
 245 .. clicmd:: isis three-way-handshake
 246
 247    Enable or disable :rfc:`5303` Three-Way Handshake for P2P adjacencies.
 248    Three-Way Handshake is enabled by default.
 249
 250 .. clicmd:: isis fast-reroute lfa [level-1 | level-2]
 251
 252    Enable per-prefix local LFA fast reroute link protection.
 253
 254 .. clicmd:: isis fast-reroute lfa [level-1 | level-2] exclude interface IFNAME
 255
 256    Exclude an interface from the local LFA backup nexthop computation.
 257
 258 .. clicmd:: isis fast-reroute remote-lfa tunnel mpls-ldp [level-1 | level-2]
 259
 260    Enable per-prefix Remote LFA fast reroute link protection. Note that other
 261    routers in the network need to be configured to accept LDP targeted hello
 262    messages in order for RLFA to work.
 263
 264 .. clicmd:: isis fast-reroute remote-lfa maximum-metric (1-16777215) [level-1 | level-2]
 265
 266    Limit Remote LFA PQ node selection within the specified metric.
 267
 268 .. clicmd:: isis fast-reroute ti-lfa [level-1|level-2] [node-protection [link-fallback]]
 269
 270    Enable per-prefix TI-LFA fast reroute link or node protection.
 271    When node protection is used, option link-fallback enables the computation and use of
 272    link-protecting LFAs for destinations unprotected by node protection.
 273
 274 .. _showing-isis-information:
 275
 276 Showing ISIS information
 277 ========================
 278
 279 .. clicmd:: show isis [vrf <NAME|all>] summary [json]
 280
 281    Show summary information about ISIS.
 282
 283 .. clicmd:: show isis hostname
 284
 285    Show information about ISIS node.
 286
 287 .. clicmd:: show isis [vrf <NAME|all>] interface [detail] [IFNAME] [json]
 288
 289    Show state and configuration of ISIS specified interface, or all interfaces
 290    if no interface is given with or without details.
 291
 292 .. clicmd:: show isis [vrf <NAME|all>] neighbor [detail] [SYSTEMID] [json]
 293
 294    Show state and information of ISIS specified neighbor, or all neighbors if
 295    no system id is given with or without details.
 296
 297 .. clicmd:: show isis [vrf <NAME|all>] database [detail] [LSPID] [json]
 298
 299    Show the ISIS database globally, for a specific LSP id without or with
 300    details.
 301
 302 .. clicmd:: show isis topology [level-1|level-2]
 303
 304    Show topology IS-IS paths to Intermediate Systems, globally, in area
 305    (level-1) or domain (level-2).
 306
 307 .. clicmd:: show isis route [level-1|level-2] [prefix-sid|backup]
 308
 309    Show the ISIS routing table, as determined by the most recent SPF
 310    calculation.
 311
 312 .. clicmd:: show isis fast-reroute summary [level-1|level-2]
 313
 314    Show information about the number of prefixes having LFA protection,
 315    and network-wide LFA coverage.
 316
 317
 318 .. _isis-traffic-engineering:
 319
 320 Traffic Engineering
 321 ===================
 322
 323 .. note::
 324
 325    IS-IS-TE supports RFC 5305 (base TE), RFC 6119 (IPv6) and RFC 7810 / 8570
 326    (Extended Metric) with or without Multi-Topology. All Traffic Engineering
 327    information are stored in a database formally named TED. However, best
 328    acccuracy is provided without Multi-Topology due to inconsistency of Traffic
 329    Engineering Advertisement of 3rd party commercial routers when MT is enabled.
 330    At this time, FRR offers partial support for some of the routing protocol
 331    extensions that can be used with MPLS-TE. FRR does not currently support a
 332    complete RSVP-TE solution.
 333
 334 .. clicmd:: mpls-te on
 335
 336    Enable Traffic Engineering LSP flooding.
 337
 338 .. clicmd:: mpls-te router-address <A.B.C.D>
 339
 340    Configure stable IP address for MPLS-TE.
 341
 342 .. clicmd:: mpls-te router-address ipv6 <X:X::X:X>
 343
 344    Configure stable IPv6 address for MPLS-TE.
 345
 346 .. clicmd:: mpls-te export
 347
 348    Export Traffic Engineering DataBase to other daemons through the ZAPI
 349    Opaque Link State messages.
 350
 351 .. clicmd:: show isis mpls-te interface
 352
 353 .. clicmd:: show isis mpls-te interface INTERFACE
 354
 355    Show MPLS Traffic Engineering parameters for all or specified interface.
 356
 357 .. clicmd:: show isis mpls-te router
 358
 359    Show Traffic Engineering router parameters.
 360
 361 .. clicmd:: show isis [vrf <NAME|all>] mpls-te database [detail|json]
 362
 363 .. clicmd:: show isis [vrf <NAME|all>] mpls-te database vertex [WORD] [detail|json]
 364
 365 .. clicmd:: show isis [vrf <NAME|all>] mpls-te database edge [A.B.C.D|X:X::X:X] [detail|json]
 366
 367 .. clicmd:: show isis [vrf <NAME|all>] mpls-te database subnet [A.B.C.D/M|X:X::X:X/M] [detail|json]
 368
 369    Show Traffic Engineering Database
 370
 371 .. seealso::
 372
 373    :ref:`ospf-traffic-engineering`
 374
 375
 376 .. _debugging-isis:
 377
 378 Segment Routing
 379 ===============
 380
 381 This is an EXPERIMENTAL support of Segment Routing as per RFC8667
 382 for MPLS dataplane. It supports IPv4, IPv6 and ECMP and has been
 383 tested against Cisco & Juniper routers.
 384
 385 Known limitations:
 386  - No support for level redistribution (L1 to L2 or L2 to L1)
 387  - No support for binding SID
 388  - No support for SRMS
 389  - No support for SRLB
 390  - Only one SRGB and default SPF Algorithm is supported
 391
 392 .. clicmd:: segment-routing on
 393
 394    Enable Segment Routing.
 395
 396 .. clicmd:: segment-routing global-block (16-1048575) (16-1048575) [local-block (16-1048575) (16-1048575)]
 397
 398    Set the Segment Routing Global Block i.e. the label range used by MPLS
 399    to store label in the MPLS FIB for Prefix SID. Note that the block size
 400    may not exceed 65535. Optionally sets also the Segment Routing Local Block.
 401    The negative command always unsets both.
 402
 403 .. clicmd:: segment-routing node-msd (1-16)
 404
 405    Set the Maximum Stack Depth supported by the router. The value depend of the
 406    MPLS dataplane. E.g. for Linux kernel, since version 4.13 the maximum value
 407    is 32.
 408
 409 .. clicmd:: segment-routing prefix <A.B.C.D/M|X:X::X:X/M> <absolute (16-1048575)|index (0-65535) [no-php-flag|explicit-null] [n-flag-clear]
 410
 411    prefix. The 'no-php-flag' means NO Penultimate Hop Popping that allows SR
 412    node to request to its neighbor to not pop the label. The 'explicit-null'
 413    flag allows SR node to request to its neighbor to send IP packet with the
 414    EXPLICIT-NULL label. The 'n-flag-clear' option can be used to explicitly
 415    clear the Node flag that is set by default for Prefix-SIDs associated to
 416    loopback addresses. This option is necessary to configure Anycast-SIDs.
 417
 418 .. clicmd:: show isis segment-routing node
 419
 420    Show detailed information about all learned Segment Routing Nodes.
 421
 422 Debugging ISIS
 423 ==============
 424
 425 .. clicmd:: debug isis adj-packets
 426
 427    IS-IS Adjacency related packets.
 428
 429 .. clicmd:: debug isis checksum-errors
 430
 431    IS-IS LSP checksum errors.
 432
 433 .. clicmd:: debug isis events
 434
 435    IS-IS Events.
 436
 437 .. clicmd:: debug isis local-updates
 438
 439    IS-IS local update packets.
 440
 441 .. clicmd:: debug isis packet-dump
 442
 443    IS-IS packet dump.
 444
 445 .. clicmd:: debug isis protocol-errors
 446
 447    IS-IS LSP protocol errors.
 448
 449 .. clicmd:: debug isis route-events
 450
 451    IS-IS Route related events.
 452
 453 .. clicmd:: debug isis snp-packets
 454
 455    IS-IS CSNP/PSNP packets.
 456
 457 .. clicmd:: debug isis spf-events
 458 .. clicmd:: debug isis spf-statistics
 459 .. clicmd:: debug isis spf-triggers
 460
 461    IS-IS Shortest Path First Events, Timing and Statistic Data and triggering
 462    events.
 463
 464 .. clicmd:: debug isis update-packets
 465
 466
 467    Update related packets.
 468
 469 .. clicmd:: debug isis te-events
 470
 471    IS-IS Traffic Engineering events
 472
 473 .. clicmd:: debug isis sr-events
 474
 475
 476    IS-IS Segment Routing events.
 477
 478 .. clicmd:: debug isis lfa
 479
 480
 481    IS-IS LFA events.
 482
 483 .. clicmd:: show debugging isis
 484
 485    Print which ISIS debug level is activate.
 486
 487 .. _isis-config-examples:
 488
 489 ISIS Configuration Examples
 490 ===========================
 491
 492 A simple example, with MD5 authentication enabled:
 493
 494 .. code-block:: frr
 495
 496    !
 497    interface eth0
 498     ip router isis FOO
 499     isis network point-to-point
 500     isis circuit-type level-2-only
 501    !
 502    router isis FOO
 503    net 47.0023.0000.0000.0000.0000.0000.0000.1900.0004.00
 504     metric-style wide
 505     is-type level-2-only
 506
 507
 508 A Traffic Engineering configuration, with Inter-ASv2 support.
 509
 510 First, the :file:`zebra.conf` part:
 511
 512 .. code-block:: frr
 513
 514    hostname HOSTNAME
 515    password PASSWORD
 516    log file /var/log/zebra.log
 517    !
 518    interface eth0
 519     ip address 10.2.2.2/24
 520     link-params
 521      max-bw 1.25e+07
 522      max-rsv-bw 1.25e+06
 523      unrsv-bw 0 1.25e+06
 524      unrsv-bw 1 1.25e+06
 525      unrsv-bw 2 1.25e+06
 526      unrsv-bw 3 1.25e+06
 527      unrsv-bw 4 1.25e+06
 528      unrsv-bw 5 1.25e+06
 529      unrsv-bw 6 1.25e+06
 530      unrsv-bw 7 1.25e+06
 531      admin-grp 0xab
 532    !
 533    interface eth1
 534     ip address 10.1.1.1/24
 535     link-params
 536      enable
 537      metric 100
 538      max-bw 1.25e+07
 539      max-rsv-bw 1.25e+06
 540      unrsv-bw 0 1.25e+06
 541      unrsv-bw 1 1.25e+06
 542      unrsv-bw 2 1.25e+06
 543      unrsv-bw 3 1.25e+06
 544      unrsv-bw 4 1.25e+06
 545      unrsv-bw 5 1.25e+06
 546      unrsv-bw 6 1.25e+06
 547      unrsv-bw 7 1.25e+06
 548      neighbor 10.1.1.2 as 65000
 549
 550
 551 Then the :file:`isisd.conf` itself:
 552
 553 .. code-block:: frr
 554
 555    hostname HOSTNAME
 556    password PASSWORD
 557    log file /var/log/isisd.log
 558    !
 559    !
 560    interface eth0
 561     ip router isis FOO
 562    !
 563    interface eth1
 564     ip router isis FOO
 565    !
 566    !
 567    router isis FOO
 568     isis net 47.0023.0000.0000.0000.0000.0000.0000.1900.0004.00
 569      mpls-te on
 570      mpls-te router-address 10.1.1.1
 571    !
 572    line vty
 573
 574 A Segment Routing configuration, with IPv4, IPv6, SRGB and MSD configuration.
 575
 576 .. code-block:: frr
 577
 578    hostname HOSTNAME
 579    password PASSWORD
 580    log file /var/log/isisd.log
 581    !
 582    !
 583    interface eth0
 584     ip router isis SR
 585     isis network point-to-point
 586    !
 587    interface eth1
 588     ip router isis SR
 589    !
 590    !
 591    router isis SR
 592     net 49.0000.0000.0000.0001.00
 593     is-type level-1
 594     topology ipv6-unicast
 595     lsp-gen-interval 2
 596     segment-routing on
 597     segment-routing node-msd 8
 598     segment-routing prefix 10.1.1.1/32 index 100 explicit-null
 599     segment-routing prefix 2001:db8:1000::1/128 index 101 explicit-null
 600    !
 601
 602
 603 .. _isis-vrf-config-examples:
 604
 605 ISIS Vrf Configuration Examples
 606 ===============================
 607
 608 A simple vrf example:
 609
 610 .. code-block:: frr
 611
 612    !
 613    interface eth0 vrf RED
 614     ip router isis FOO vrf RED
 615     isis network point-to-point
 616     isis circuit-type level-2-only
 617    !
 618    router isis FOO vrf RED
 619     net 47.0023.0000.0000.0000.0000.0000.0000.1900.0004.00
 620     metric-style wide
 621     is-type level-2-only