Cisco 10000-2P2-2DC Software Guide - Page 141

Monitoring and Maintaining BGP Multipath Load Sharing for eBGP and iBGP, IPv6 VPN over MPLS

Page 141 highlights

Chapter 4 Configuring Multiprotocol Label Switching IPv6 VPN over MPLS Monitoring and Maintaining BGP Multipath Load Sharing for eBGP and iBGP To display eBGP and iBGP multipath load sharing information, enter any of the following commands in privileged EXEC mode: Command Router# show ip bgp all neighbors Router# show ip bgp vpnv4 all ip-prefix/length Router# show ip bgp vpnv4 all labels Router# show ip bgp vpnv4 rd route-distinguisher Router# show ip bgp vpnv4 all summary Router# show ip bgp vpnv4 vrf vrf-name Router# show ip route vrf vrf-name ip-prefix Purpose Displays information about the TCP and BGP connections to neighbors. Displays attributes and multipaths for a network in an MPLS VPN. The ip-prefix option is an IP prefix address (in dotted decimal format) and the length option is the length of the mask (0 to 32). You must include the slash mark when you use the length option. Displays incoming and outgoing BGP labels for each NLRI prefix. Displays Network Layer Reachability Information (NLRI) prefixes that have a matching route distinguisher. Displays BGP neighbor status. Displays NLRI prefixes associated with the named virtual routing and forwarding instance (VRF). Displays routing information for a network in an MPLS VPN. IPv6 VPN over MPLS Multiprotocol BGP is the centerpiece of the MPLS IPv6 VPN architecture in IPv4 and IPv6. It is used to distribute IPv6 routes over the service provider backbone, with the same set of mechanisms to work with overlapping addresses, redistribution policies, and scalability issues. The 6VPE feature is the IOS implementation as described in RFC 4659. IPv6 avoids overlapping address space by using either a global IPv6 Unicast prefix-RFC 3587-or Unique IPv6 Local Addressing-RFC 4193. For redistribution, a Network Layer Reachability Information (NLRI) 3-tuple, format-containing length, IPv6 prefix, and label-is defined to distribute routes using multiprotocol BGP. The extended community attribute-the route target-is used to control redistribution of routing information by tagging exported routes and filtering imported ones. For scalability, route reflectors can be used to concentrate routing paths and avoid a full PE mesh. Similar to IPv4, BGP features in IPv6, such as route refresh, automatic route filtering, and outbound route filtering, help reduce the number of routes held in each PE. Figure 4-1 illustrates the important aspects of the IPv6 VPN architecture. OL-2226-23 Cisco 10000 Series Router Software Configuration Guide 4-7

  • 1
  • 2
  • 3
  • 4
  • 5
  • 6
  • 7
  • 8
  • 9
  • 10
  • 11
  • 12
  • 13
  • 14
  • 15
  • 16
  • 17
  • 18
  • 19
  • 20
  • 21
  • 22
  • 23
  • 24
  • 25
  • 26
  • 27
  • 28
  • 29
  • 30
  • 31
  • 32
  • 33
  • 34
  • 35
  • 36
  • 37
  • 38
  • 39
  • 40
  • 41
  • 42
  • 43
  • 44
  • 45
  • 46
  • 47
  • 48
  • 49
  • 50
  • 51
  • 52
  • 53
  • 54
  • 55
  • 56
  • 57
  • 58
  • 59
  • 60
  • 61
  • 62
  • 63
  • 64
  • 65
  • 66
  • 67
  • 68
  • 69
  • 70
  • 71
  • 72
  • 73
  • 74
  • 75
  • 76
  • 77
  • 78
  • 79
  • 80
  • 81
  • 82
  • 83
  • 84
  • 85
  • 86
  • 87
  • 88
  • 89
  • 90
  • 91
  • 92
  • 93
  • 94
  • 95
  • 96
  • 97
  • 98
  • 99
  • 100
  • 101
  • 102
  • 103
  • 104
  • 105
  • 106
  • 107
  • 108
  • 109
  • 110
  • 111
  • 112
  • 113
  • 114
  • 115
  • 116
  • 117
  • 118
  • 119
  • 120
  • 121
  • 122
  • 123
  • 124
  • 125
  • 126
  • 127
  • 128
  • 129
  • 130
  • 131
  • 132
  • 133
  • 134
  • 135
  • 136
  • 137
  • 138
  • 139
  • 140
  • 141
  • 142
  • 143
  • 144
  • 145
  • 146
  • 147
  • 148
  • 149
  • 150
  • 151
  • 152
  • 153
  • 154
  • 155
  • 156
  • 157
  • 158
  • 159
  • 160
  • 161
  • 162
  • 163
  • 164
  • 165
  • 166
  • 167
  • 168
  • 169
  • 170
  • 171
  • 172
  • 173
  • 174
  • 175
  • 176
  • 177
  • 178
  • 179
  • 180
  • 181
  • 182
  • 183
  • 184
  • 185
  • 186
  • 187
  • 188
  • 189
  • 190
  • 191
  • 192
  • 193
  • 194
  • 195
  • 196
  • 197
  • 198
  • 199
  • 200
  • 201
  • 202
  • 203
  • 204
  • 205
  • 206
  • 207
  • 208
  • 209
  • 210
  • 211
  • 212
  • 213
  • 214
  • 215
  • 216
  • 217
  • 218
  • 219
  • 220
  • 221
  • 222
  • 223
  • 224
  • 225
  • 226
  • 227
  • 228
  • 229
  • 230
  • 231
  • 232
  • 233
  • 234
  • 235
  • 236
  • 237
  • 238
  • 239
  • 240
  • 241
  • 242
  • 243
  • 244
  • 245
  • 246
  • 247
  • 248
  • 249
  • 250
  • 251
  • 252
  • 253
  • 254
  • 255
  • 256
  • 257
  • 258
  • 259
  • 260
  • 261
  • 262
  • 263
  • 264
  • 265
  • 266
  • 267
  • 268
  • 269
  • 270
  • 271
  • 272
  • 273
  • 274
  • 275
  • 276
  • 277
  • 278
  • 279
  • 280
  • 281
  • 282
  • 283
  • 284
  • 285
  • 286
  • 287
  • 288
  • 289
  • 290
  • 291
  • 292
  • 293
  • 294
  • 295
  • 296
  • 297
  • 298
  • 299
  • 300
  • 301
  • 302
  • 303
  • 304
  • 305
  • 306
  • 307
  • 308
  • 309
  • 310
  • 311
  • 312
  • 313
  • 314
  • 315
  • 316
  • 317
  • 318
  • 319
  • 320
  • 321
  • 322
  • 323
  • 324
  • 325
  • 326
  • 327
  • 328
  • 329
  • 330
  • 331
  • 332
  • 333
  • 334
  • 335
  • 336
  • 337
  • 338
  • 339
  • 340
  • 341
  • 342
  • 343
  • 344
  • 345
  • 346
  • 347
  • 348
  • 349
  • 350
  • 351
  • 352
  • 353
  • 354
  • 355
  • 356
  • 357
  • 358
  • 359
  • 360
  • 361
  • 362
  • 363
  • 364
  • 365
  • 366
  • 367
  • 368
  • 369
  • 370
  • 371
  • 372
  • 373
  • 374
  • 375
  • 376
  • 377
  • 378
  • 379
  • 380
  • 381
  • 382
  • 383
  • 384
  • 385
  • 386
  • 387
  • 388
  • 389
  • 390
  • 391
  • 392
  • 393
  • 394
  • 395
  • 396
  • 397
  • 398
  • 399
  • 400
  • 401
  • 402
  • 403
  • 404
  • 405
  • 406
  • 407
  • 408
  • 409
  • 410
  • 411
  • 412
  • 413
  • 414
  • 415
  • 416
  • 417
  • 418
  • 419
  • 420
  • 421
  • 422
  • 423
  • 424
  • 425
  • 426
  • 427
  • 428
  • 429
  • 430
  • 431
  • 432
  • 433
  • 434
  • 435
  • 436
  • 437
  • 438
  • 439
  • 440
  • 441
  • 442
  • 443
  • 444
  • 445
  • 446
  • 447
  • 448
  • 449
  • 450
  • 451
  • 452
  • 453
  • 454
  • 455
  • 456
  • 457
  • 458
  • 459
  • 460
  • 461
  • 462
  • 463
  • 464
  • 465
  • 466
  • 467
  • 468
  • 469
  • 470
  • 471
  • 472
  • 473
  • 474
  • 475
  • 476
  • 477
  • 478
  • 479
  • 480
  • 481
  • 482
  • 483
  • 484
  • 485
  • 486
  • 487
  • 488
  • 489
  • 490
  • 491
  • 492
  • 493
  • 494
  • 495
  • 496
  • 497
  • 498
  • 499
  • 500
  • 501
  • 502
  • 503
  • 504
  • 505
  • 506
  • 507
  • 508
  • 509
  • 510
  • 511
  • 512
  • 513
  • 514
  • 515
  • 516
  • 517
  • 518
  • 519
  • 520
  • 521
  • 522
  • 523
  • 524
  • 525
  • 526
  • 527
  • 528
  • 529
  • 530
  • 531
  • 532
  • 533
  • 534
  • 535
  • 536
  • 537
  • 538
  • 539
  • 540
  • 541
  • 542
  • 543
  • 544
  • 545
  • 546
  • 547
  • 548
  • 549
  • 550
  • 551
  • 552
  • 553
  • 554
  • 555
  • 556
  • 557
  • 558
  • 559
  • 560
  • 561
  • 562
  • 563
  • 564
  • 565
  • 566
  • 567
  • 568
  • 569
  • 570
  • 571
  • 572
  • 573
  • 574
  • 575
  • 576
  • 577
  • 578
  • 579
  • 580
  • 581
  • 582
  • 583
  • 584
  • 585
  • 586
  • 587
  • 588
  • 589
  • 590
  • 591
  • 592
  • 593
  • 594
  • 595
  • 596
  • 597
  • 598
  • 599
  • 600
  • 601
  • 602
  • 603
  • 604
  • 605
  • 606
  • 607
  • 608
  • 609
  • 610
  • 611
  • 612
  • 613
  • 614
  • 615
  • 616
  • 617
  • 618
  • 619
  • 620
  • 621
  • 622
  • 623
  • 624

4-7
Cisco 10000 Series Router Software Configuration Guide
OL-2226-23
Chapter 4
Configuring Multiprotocol Label Switching
IPv6 VPN over MPLS
Monitoring and Maintaining BGP Multipath Load Sharing for eBGP and iBGP
To display eBGP and iBGP multipath load sharing information, enter any of the following commands in
privileged EXEC mode:
IPv6 VPN over MPLS
Multiprotocol BGP is the centerpiece of the MPLS IPv6 VPN architecture in IPv4 and IPv6. It is used
to distribute IPv6 routes over the service provider backbone, with the same set of mechanisms to work
with overlapping addresses, redistribution policies, and scalability issues. The 6VPE feature is the IOS
implementation as described in RFC 4659.
IPv6 avoids overlapping address space by using either a global IPv6 Unicast prefix
RFC 3587
or
Unique IPv6 Local Addressing
RFC 4193. For redistribution, a Network Layer Reachability
Information (NLRI) 3-tuple, format—containing length, IPv6 prefix, and label—is defined to distribute
routes using multiprotocol BGP. The extended community attribute—the route target—is used to control
redistribution of routing information by tagging exported routes and filtering imported ones.
For scalability, route reflectors can be used to concentrate routing paths and avoid a full PE mesh.
Similar to IPv4, BGP features in IPv6, such as route refresh, automatic route filtering, and outbound
route filtering, help reduce the number of routes held in each PE.
Figure 4-1
illustrates the important aspects of the IPv6 VPN architecture.
Command
Purpose
Router#
show ip bgp all neighbors
Displays information about the TCP and BGP connections to
neighbors.
Router#
show ip bgp vpnv4 all
ip-prefix
/
length
Displays attributes and multipaths for a network in an MPLS
VPN.
The
ip-prefix
option is an IP prefix address (in dotted decimal
format) and the
length
option is the length of the mask (0 to 32).
You must include the slash mark when you use the
length
option.
Router#
show ip bgp vpnv4 all labels
Displays incoming and outgoing BGP labels for each NLRI
prefix.
Router#
show ip bgp vpnv4 rd
route-distinguisher
Displays Network Layer Reachability Information (NLRI)
prefixes that have a matching route distinguisher.
Router#
show ip bgp vpnv4 all summary
Displays BGP neighbor status.
Router#
show ip bgp vpnv4 vrf
vrf-name
Displays NLRI prefixes associated with the named virtual routing
and forwarding instance (VRF).
Router#
show ip route vrf
vrf-name ip-prefix
Displays routing information for a network in an MPLS VPN.