doc/developer/zebra.rst

   1 .. _zebra:
   2
   3 *****
   4 Zebra
   5 *****
   6
   7 .. _zebra-protocol:
   8
   9 Overview of the Zebra Protocol
  10 ==============================
  11
  12 The Zebra protocol (or ``ZAPI``) is used by protocol daemons to
  13 communicate with the **zebra** daemon.
  14
  15 Each protocol daemon may request and send information to and from the
  16 **zebra** daemon such as interface states, routing state,
  17 nexthop-validation, and so on.  Protocol daemons may also install
  18 routes with **zebra**. The **zebra** daemon manages which routes are
  19 installed into the forwarding table with the kernel. Some daemons use
  20 more than one ZAPI connection. This is supported: each ZAPI session is
  21 identified by a tuple of: ``{protocol, instance, session_id}``. LDPD
  22 is an example: it uses a second, synchronous ZAPI session to manage
  23 label blocks. The default value for ``session_id`` is zero; daemons
  24 who use multiple ZAPI sessions must assign unique values to the
  25 sessions' ids.
  26
  27 The Zebra protocol is a streaming protocol, with a common header. Version 0
  28 lacks a version field and is implicitly versioned. Version 1 and all subsequent
  29 versions have a version field.  Version 0 can be distinguished from all other
  30 versions by examining the 3rd byte of the header, which contains a marker value
  31 of 255 (in Quagga) or 254 (in FRR) for all versions except version 0. The
  32 marker byte corresponds to the command field in version 0, and the marker value
  33 is a reserved command in version 0.
  34
  35 Version History
  36 ---------------
  37
  38 - Version 0
  39
  40   Used by all versions of GNU Zebra and all version of Quagga up to and
  41   including Quagga 0.98. This version has no ``version`` field, and so is
  42   implicitly versioned as version 0.
  43
  44 - Version 1
  45
  46   Added ``marker`` and ``version`` fields, increased ``command`` field to 16
  47   bits. Used by Quagga versions 0.99.3 through 0.99.20.
  48
  49 - Version 2
  50
  51   Used by Quagga versions 0.99.21 through 0.99.23.
  52
  53 - Version 3
  54
  55   Added ``vrf_id`` field. Used by Quagga versions 0.99.23 until FRR fork.
  56
  57 - Version 4
  58
  59   Change marker value to 254 to prevent people mixing and matching Quagga and
  60   FRR daemon binaries. Used by FRR versions 2.0 through 3.0.3.
  61
  62 - Version 5
  63
  64   Increased VRF identifier field from 16 to 32 bits. Used by FRR versions 4.0
  65   through 5.0.1.
  66
  67 - Version 6
  68
  69   Removed the following commands:
  70
  71   * ZEBRA_IPV4_ROUTE_ADD
  72   * ZEBRA_IPV4_ROUTE_DELETE
  73   * ZEBRA_IPV6_ROUTE_ADD
  74   * ZEBRA_IPV6_ROUTE_DELETE
  75
  76   Used since FRR version 6.0.
  77
  78
  79 Zebra Protocol Definition
  80 =========================
  81
  82 Zebra Protocol Header Field Definitions
  83 ---------------------------------------
  84
  85 Length
  86    Total packet length including this header.
  87
  88 Marker
  89    Static marker. The marker value, when it exists, is 255 in all versions of
  90    Quagga. It is 254 in all versions of FRR. This is to allow version 0 headers
  91    (which do not include version explicitly) to be distinguished from versioned
  92    headers.
  93
  94 Version
  95    Zebra protocol version number. Clients should not continue processing
  96    messages past the version field for versions they do not recognise.
  97
  98 Command
  99    The Zebra protocol command.
 100
 101
 102 Current Version
 103 ^^^^^^^^^^^^^^^
 104
 105 ::
 106
 107    Version 5, 6
 108
 109     0                   1                   2                   3
 110     0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 111    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 112    |             Length            |     Marker    |    Version    |
 113    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 114    |                             VRF ID                            |
 115    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 116    |            Command            |
 117    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 118
 119
 120 Past Versions
 121 ^^^^^^^^^^^^^
 122
 123 ::
 124
 125    Version 0
 126
 127     0                   1                   2                   3
 128     0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 129    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 130    |             Length            |    Command    |
 131    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 132
 133 ::
 134
 135    Version 1, 2
 136
 137     0                   1                   2                   3
 138     0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 139    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 140    |             Length            |     Marker    |    Version    |
 141    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 142    |            Command            |
 143    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 144
 145
 146 ::
 147
 148    Version 3, 4
 149
 150     0                   1                   2                   3
 151     0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 152    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 153    |             Length            |     Marker    |    Version    |
 154    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 155    |             VRF ID            |            Command            |
 156    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 157
 158
 159 Zebra Protocol Commands
 160 -----------------------
 161
 162 +------------------------------------+-------+
 163 | Command                            | Value |
 164 +====================================+=======+
 165 | ZEBRA_INTERFACE_ADD                | 0     |
 166 +------------------------------------+-------+
 167 | ZEBRA_INTERFACE_DELETE             | 1     |
 168 +------------------------------------+-------+
 169 | ZEBRA_INTERFACE_ADDRESS_ADD        | 2     |
 170 +------------------------------------+-------+
 171 | ZEBRA_INTERFACE_ADDRESS_DELETE     | 3     |
 172 +------------------------------------+-------+
 173 | ZEBRA_INTERFACE_UP                 | 4     |
 174 +------------------------------------+-------+
 175 | ZEBRA_INTERFACE_DOWN               | 5     |
 176 +------------------------------------+-------+
 177 | ZEBRA_INTERFACE_SET_MASTER         | 6     |
 178 +------------------------------------+-------+
 179 | ZEBRA_INTERFACE_SET_PROTODOWN      | 7     |
 180 +------------------------------------+-------+
 181 | ZEBRA_ROUTE_ADD                    | 8     |
 182 +------------------------------------+-------+
 183 | ZEBRA_ROUTE_DELETE                 | 9     |
 184 +------------------------------------+-------+
 185 | ZEBRA_ROUTE_NOTIFY_OWNER           | 10    |
 186 +------------------------------------+-------+
 187 | ZEBRA_REDISTRIBUTE_ADD             | 11    |
 188 +------------------------------------+-------+
 189 | ZEBRA_REDISTRIBUTE_DELETE          | 12    |
 190 +------------------------------------+-------+
 191 | ZEBRA_REDISTRIBUTE_DEFAULT_ADD     | 13    |
 192 +------------------------------------+-------+
 193 | ZEBRA_REDISTRIBUTE_DEFAULT_DELETE  | 14    |
 194 +------------------------------------+-------+
 195 | ZEBRA_ROUTER_ID_ADD                | 15    |
 196 +------------------------------------+-------+
 197 | ZEBRA_ROUTER_ID_DELETE             | 16    |
 198 +------------------------------------+-------+
 199 | ZEBRA_ROUTER_ID_UPDATE             | 17    |
 200 +------------------------------------+-------+
 201 | ZEBRA_HELLO                        | 18    |
 202 +------------------------------------+-------+
 203 | ZEBRA_CAPABILITIES                 | 19    |
 204 +------------------------------------+-------+
 205 | ZEBRA_NEXTHOP_REGISTER             | 20    |
 206 +------------------------------------+-------+
 207 | ZEBRA_NEXTHOP_UNREGISTER           | 21    |
 208 +------------------------------------+-------+
 209 | ZEBRA_NEXTHOP_UPDATE               | 22    |
 210 +------------------------------------+-------+
 211 | ZEBRA_INTERFACE_NBR_ADDRESS_ADD    | 23    |
 212 +------------------------------------+-------+
 213 | ZEBRA_INTERFACE_NBR_ADDRESS_DELETE | 24    |
 214 +------------------------------------+-------+
 215 | ZEBRA_INTERFACE_BFD_DEST_UPDATE    | 25    |
 216 +------------------------------------+-------+
 217 | ZEBRA_IMPORT_ROUTE_REGISTER        | 26    |
 218 +------------------------------------+-------+
 219 | ZEBRA_IMPORT_ROUTE_UNREGISTER      | 27    |
 220 +------------------------------------+-------+
 221 | ZEBRA_IMPORT_CHECK_UPDATE          | 28    |
 222 +------------------------------------+-------+
 223 | ZEBRA_BFD_DEST_REGISTER            | 29    |
 224 +------------------------------------+-------+
 225 | ZEBRA_BFD_DEST_DEREGISTER          | 30    |
 226 +------------------------------------+-------+
 227 | ZEBRA_BFD_DEST_UPDATE              | 31    |
 228 +------------------------------------+-------+
 229 | ZEBRA_BFD_DEST_REPLAY              | 32    |
 230 +------------------------------------+-------+
 231 | ZEBRA_REDISTRIBUTE_ROUTE_ADD       | 33    |
 232 +------------------------------------+-------+
 233 | ZEBRA_REDISTRIBUTE_ROUTE_DEL       | 34    |
 234 +------------------------------------+-------+
 235 | ZEBRA_VRF_UNREGISTER               | 35    |
 236 +------------------------------------+-------+
 237 | ZEBRA_VRF_ADD                      | 36    |
 238 +------------------------------------+-------+
 239 | ZEBRA_VRF_DELETE                   | 37    |
 240 +------------------------------------+-------+
 241 | ZEBRA_VRF_LABEL                    | 38    |
 242 +------------------------------------+-------+
 243 | ZEBRA_INTERFACE_VRF_UPDATE         | 39    |
 244 +------------------------------------+-------+
 245 | ZEBRA_BFD_CLIENT_REGISTER          | 40    |
 246 +------------------------------------+-------+
 247 | ZEBRA_BFD_CLIENT_DEREGISTER        | 41    |
 248 +------------------------------------+-------+
 249 | ZEBRA_INTERFACE_ENABLE_RADV        | 42    |
 250 +------------------------------------+-------+
 251 | ZEBRA_INTERFACE_DISABLE_RADV       | 43    |
 252 +------------------------------------+-------+
 253 | ZEBRA_IPV4_NEXTHOP_LOOKUP_MRIB     | 44    |
 254 +------------------------------------+-------+
 255 | ZEBRA_INTERFACE_LINK_PARAMS        | 45    |
 256 +------------------------------------+-------+
 257 | ZEBRA_MPLS_LABELS_ADD              | 46    |
 258 +------------------------------------+-------+
 259 | ZEBRA_MPLS_LABELS_DELETE           | 47    |
 260 +------------------------------------+-------+
 261 | ZEBRA_MPLS_LABELS_REPLACE          | 48    |
 262 +------------------------------------+-------+
 263 | ZEBRA_IPMR_ROUTE_STATS             | 49    |
 264 +------------------------------------+-------+
 265 | ZEBRA_LABEL_MANAGER_CONNECT        | 50    |
 266 +------------------------------------+-------+
 267 | ZEBRA_LABEL_MANAGER_CONNECT_ASYNC  | 51    |
 268 +------------------------------------+-------+
 269 | ZEBRA_GET_LABEL_CHUNK              | 52    |
 270 +------------------------------------+-------+
 271 | ZEBRA_RELEASE_LABEL_CHUNK          | 53    |
 272 +------------------------------------+-------+
 273 | ZEBRA_FEC_REGISTER                 | 54    |
 274 +------------------------------------+-------+
 275 | ZEBRA_FEC_UNREGISTER               | 55    |
 276 +------------------------------------+-------+
 277 | ZEBRA_FEC_UPDATE                   | 56    |
 278 +------------------------------------+-------+
 279 | ZEBRA_ADVERTISE_DEFAULT_GW         | 57    |
 280 +------------------------------------+-------+
 281 | ZEBRA_ADVERTISE_SVI_MACIP          | 58    |
 282 +------------------------------------+-------+
 283 | ZEBRA_ADVERTISE_SUBNET             | 59    |
 284 +------------------------------------+-------+
 285 | ZEBRA_ADVERTISE_ALL_VNI            | 60    |
 286 +------------------------------------+-------+
 287 | ZEBRA_LOCAL_ES_ADD                 | 61    |
 288 +------------------------------------+-------+
 289 | ZEBRA_LOCAL_ES_DEL                 | 62    |
 290 +------------------------------------+-------+
 291 | ZEBRA_VNI_ADD                      | 63    |
 292 +------------------------------------+-------+
 293 | ZEBRA_VNI_DEL                      | 64    |
 294 +------------------------------------+-------+
 295 | ZEBRA_L3VNI_ADD                    | 65    |
 296 +------------------------------------+-------+
 297 | ZEBRA_L3VNI_DEL                    | 66    |
 298 +------------------------------------+-------+
 299 | ZEBRA_REMOTE_VTEP_ADD              | 67    |
 300 +------------------------------------+-------+
 301 | ZEBRA_REMOTE_VTEP_DEL              | 68    |
 302 +------------------------------------+-------+
 303 | ZEBRA_MACIP_ADD                    | 69    |
 304 +------------------------------------+-------+
 305 | ZEBRA_MACIP_DEL                    | 70    |
 306 +------------------------------------+-------+
 307 | ZEBRA_IP_PREFIX_ROUTE_ADD          | 71    |
 308 +------------------------------------+-------+
 309 | ZEBRA_IP_PREFIX_ROUTE_DEL          | 72    |
 310 +------------------------------------+-------+
 311 | ZEBRA_REMOTE_MACIP_ADD             | 73    |
 312 +------------------------------------+-------+
 313 | ZEBRA_REMOTE_MACIP_DEL             | 74    |
 314 +------------------------------------+-------+
 315 | ZEBRA_DUPLICATE_ADDR_DETECTION     | 75    |
 316 +------------------------------------+-------+
 317 | ZEBRA_PW_ADD                       | 76    |
 318 +------------------------------------+-------+
 319 | ZEBRA_PW_DELETE                    | 77    |
 320 +------------------------------------+-------+
 321 | ZEBRA_PW_SET                       | 78    |
 322 +------------------------------------+-------+
 323 | ZEBRA_PW_UNSET                     | 79    |
 324 +------------------------------------+-------+
 325 | ZEBRA_PW_STATUS_UPDATE             | 80    |
 326 +------------------------------------+-------+
 327 | ZEBRA_RULE_ADD                     | 81    |
 328 +------------------------------------+-------+
 329 | ZEBRA_RULE_DELETE                  | 82    |
 330 +------------------------------------+-------+
 331 | ZEBRA_RULE_NOTIFY_OWNER            | 83    |
 332 +------------------------------------+-------+
 333 | ZEBRA_TABLE_MANAGER_CONNECT        | 84    |
 334 +------------------------------------+-------+
 335 | ZEBRA_GET_TABLE_CHUNK              | 85    |
 336 +------------------------------------+-------+
 337 | ZEBRA_RELEASE_TABLE_CHUNK          | 86    |
 338 +------------------------------------+-------+
 339 | ZEBRA_IPSET_CREATE                 | 87    |
 340 +------------------------------------+-------+
 341 | ZEBRA_IPSET_DESTROY                | 88    |
 342 +------------------------------------+-------+
 343 | ZEBRA_IPSET_ENTRY_ADD              | 89    |
 344 +------------------------------------+-------+
 345 | ZEBRA_IPSET_ENTRY_DELETE           | 90    |
 346 +------------------------------------+-------+
 347 | ZEBRA_IPSET_NOTIFY_OWNER           | 91    |
 348 +------------------------------------+-------+
 349 | ZEBRA_IPSET_ENTRY_NOTIFY_OWNER     | 92    |
 350 +------------------------------------+-------+
 351 | ZEBRA_IPTABLE_ADD                  | 93    |
 352 +------------------------------------+-------+
 353 | ZEBRA_IPTABLE_DELETE               | 94    |
 354 +------------------------------------+-------+
 355 | ZEBRA_IPTABLE_NOTIFY_OWNER         | 95    |
 356 +------------------------------------+-------+
 357 | ZEBRA_VXLAN_FLOOD_CONTROL          | 96    |
 358 +------------------------------------+-------+
 359 | ZEBRA_VXLAN_SG_ADD                 | 97    |
 360 +------------------------------------+-------+
 361 | ZEBRA_VXLAN_SG_DEL                 | 98    |
 362 +------------------------------------+-------+
 363 | ZEBRA_VXLAN_SG_REPLAY              | 99    |
 364 +------------------------------------+-------+
 365 | ZEBRA_MLAG_PROCESS_UP              | 100   |
 366 +------------------------------------+-------+
 367 | ZEBRA_MLAG_PROCESS_DOWN            | 101   |
 368 +------------------------------------+-------+
 369 | ZEBRA_MLAG_CLIENT_REGISTER         | 102   |
 370 +------------------------------------+-------+
 371 | ZEBRA_MLAG_CLIENT_UNREGISTER       | 103   |
 372 +------------------------------------+-------+
 373 | ZEBRA_MLAG_FORWARD_MSG             | 104   |
 374 +------------------------------------+-------+
 375 | ZEBRA_ERROR                        | 105   |
 376 +------------------------------------+-------+
 377 | ZEBRA_CLIENT_CAPABILITIES          | 106   |
 378 +------------------------------------+-------+
 379 | ZEBRA_OPAQUE_MESSAGE               | 107   |
 380 +------------------------------------+-------+
 381 | ZEBRA_OPAQUE_REGISTER              | 108   |
 382 +------------------------------------+-------+
 383 | ZEBRA_OPAQUE_UNREGISTER            | 109   |
 384 +------------------------------------+-------+