Brocade Communications Systems FastIron SX 800 Configuration Manual page 10

Configuring BGP4 (IPv4)............................................................................................................................................................................................. 351
BGP4 overview.....................................................................................................................................................................................................................................351
Relationship between the BGP4 route table and the IP route table......................................................................................................................352
How BGP4 selects a path for a route (BGP best path selection algorithm)...................................................................................................... 353
BGP4 message types.............................................................................................................................................................................................................. 354
Grouping of RIB-out peers.....................................................................................................................................................................................................356
Implementation of BGP4................................................................................................................................................................................................................. 356
BGP4 restart..........................................................................................................................................................................................................................................356
BGP4 Peer notification during a management module switchover......................................................................................................................357
BGP4 neighbor local AS......................................................................................................................................................................................................... 358
Basic configuration and activation for BGP4...........................................................................................................................................................................360
Disabling BGP4.......................................................................................................................................................................................................................... 361
BGP4 parameters................................................................................................................................................................................................................................361
Parameter changes that take effect immediately.......................................................................................................................................................... 363
Parameter changes that take effect after resetting neighbor sessions.................................................................................................................363
Parameter changes that take effect after disabling and re-enabling redistribution......................................................................................... 364
Memory considerations.....................................................................................................................................................................................................................364
Memory configuration options obsoleted by dynamic memory............................................................................................................................ 364
Basic configuration tasks required for BGP4...........................................................................................................................................................................364
Enabling BGP4 on the device...............................................................................................................................................................................................365
Changing the device ID............................................................................................................................................................................................................365
Setting the local AS number.................................................................................................................................................................................................. 365
Adding a loopback interface...................................................................................................................................................................................................366
Adding BGP4 neighbors.........................................................................................................................................................................................................367
Adding a BGP4 peer group................................................................................................................................................................................................... 374
Optional BGP4 configuration tasks............................................................................................................................................................................................. 377
Changing the Keep Alive Time and Hold Time..............................................................................................................................................................377
Changing the BGP4 next-hop update timer...................................................................................................................................................................377
Enabling fast external fallover................................................................................................................................................................................................ 378
Changing the maximum number of paths for BGP4 Multipath load sharing...................................................................................................378
Customizing BGP4 Multipath load sharing.....................................................................................................................................................................380
Specifying a list of networks to advertise......................................................................................................................................................................... 380
Changing the default local preference................................................................................................................................................................................381
Using the IP default route as a valid next-hop for a BGP4 route...........................................................................................................................382
Changing the default MED (Metric) used for route redistribution...........................................................................................................................382
Enabling next-hop recursion..................................................................................................................................................................................................382
Changing administrative distances......................................................................................................................................................................................385
Requiring the first AS to be the neighbor AS..................................................................................................................................................................386
Disabling or re-enabling comparison of the AS-Path length...................................................................................................................................387
Enabling or disabling comparison of device IDs........................................................................................................................................................... 387
Configuring the device to always compare Multi-Exit Discriminators.................................................................................................................. 387
Treating missing MEDs as the worst MEDs....................................................................................................................................................................388
Configuring route reflection parameters........................................................................................................................................................................... 388
Configuring confederations.................................................................................................................................................................................................... 391
Aggregating routes advertised to BGP4 neighbors.....................................................................................................................................................394
Configuring BGP4 restart.................................................................................................................................................................................................................395
Configuring BGP4 Restart for the global routing instance....................................................................................................................................... 395
Configuring BGP4 Restart for a VRF................................................................................................................................................................................ 395
Configuring timers for BGP4 Restart (optional).............................................................................................................................................................395
BGP4 null0 routing....................................................................................................................................................................................................................396
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FastIron Ethernet Switch Layer 3 Routing
53-1003627-04