Conguring BGP4 null0 routing.......................................................................................................................................................................................... 397
Modifying redistribution parameters............................................................................................................................................................................................400
Redistributing connected routes...........................................................................................................................................................................................401
Redistributing RIP routes.........................................................................................................................................................................................................401
Redistributing OSPF external routes..................................................................................................................................................................................401
Redistributing static routes......................................................................................................................................................................................................402
Redistributing IBGP routes.....................................................................................................................................................................................................402
Filtering.....................................................................................................................................................................................................................................................402
AS-path ltering..........................................................................................................................................................................................................................403
BGP4 ltering communities.................................................................................................................................................................................................. 405
Dening and applying IP prex lists....................................................................................................................................................................................407
Dening neighbor distribute lists..........................................................................................................................................................................................408
Dening route maps..................................................................................................................................................................................................................408
Using a table map to set the tag value...............................................................................................................................................................................415
Conguring cooperative BGP4 route ltering................................................................................................................................................................416
Four-byte Autonomous System Numbers (AS4).................................................................................................................................................................. 418
Enabling AS4 numbers............................................................................................................................................................................................................419
BGP4 AS4 attribute errors.............................................................................................................................................................................................................. 423
Error logs........................................................................................................................................................................................................................................423
Conguring route ap dampening................................................................................................................................................................................................424
Globally conguring route ap dampening......................................................................................................................................................................424
Using a route map to congure route ap dampening for a specic neighbor................................................................................................ 425
Removing route dampening from a route........................................................................................................................................................................426
Displaying and clearing route ap dampening statistics............................................................................................................................................ 426
Generating traps for BGP4..............................................................................................................................................................................................................428
Conguring BGP4...............................................................................................................................................................................................................................428
Entering and exiting the address family conguration level............................................................................................................................................... 429
BGP route reector............................................................................................................................................................................................................................. 430
Conguring BGP route reector...........................................................................................................................................................................................430
Specifying a maximum AS path length...................................................................................................................................................................................... 432
Setting a global maximum AS path limit.......................................................................................................................................................................... 433
Setting a maximum AS path limit for a peer group or neighbor.............................................................................................................................433
BGP4 max-as error messages......................................................................................................................................................................................................434
Maximum AS path limit error.................................................................................................................................................................................................434
Memory limit error......................................................................................................................................................................................................................434
Originating the default route............................................................................................................................................................................................................434
Changing the default metric used for route cost.....................................................................................................................................................................434
Conguring a static BGP4 network ............................................................................................................................................................................................ 435
Setting an administrative distance for a static BGP4 network.................................................................................................................................435
Limiting advertisement of a static BGP4 network to selected neighbors.......................................................................................................... 436
Dynamic route lter update.................................................................................................................................................................................................... 436
Generalized TTL Security Mechanism support...................................................................................................................................................................... 438
Displaying BGP4 information.........................................................................................................................................................................................................438
Displaying summary BGP4 information.......................................................................................................................................................................... 438
Displaying the active BGP4 conguration.......................................................................................................................................................................441
Displaying summary neighbor information..................................................................................................................................................................... 441
Displaying BGP4 neighbor information............................................................................................................................................................................443
Displaying peer group information......................................................................................................................................................................................451
Displaying summary route information............................................................................................................................................................................. 451
Displaying VRF instance information.................................................................................................................................................................................452
FastIron Ethernet Switch Layer 3 Routing
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