Reference Guide

Additional Path (Add-Path) Support........................................................................................... 194
Advertise IGP Cost as MED for Redistributed Routes................................................................ 194
Ignore Router-ID for Some Best-Path Calculations..................................................................195
Four-Byte AS Numbers............................................................................................................... 195
AS4 Number Representation...................................................................................................... 196
AS Number Migration.................................................................................................................. 197
BGP4 Management Information Base (MIB).............................................................................. 199
Important Points to Remember..................................................................................................199
Configuration Information...............................................................................................................200
BGP Configuration........................................................................................................................... 200
Enabling BGP...............................................................................................................................201
Configuring AS4 Number Representations............................................................................... 205
Configuring Peer Groups............................................................................................................207
Configuring BGP Fast Fall-Over................................................................................................. 210
Configuring Passive Peering....................................................................................................... 212
Maintaining Existing AS Numbers During an AS Migration........................................................ 212
Allowing an AS Number to Appear in its Own AS Path..............................................................213
Enabling Graceful Restart............................................................................................................214
Enabling Neighbor Graceful Restart........................................................................................... 215
Filtering on an AS-Path Attribute................................................................................................ 216
Regular Expressions as Filters......................................................................................................217
Redistributing Routes.................................................................................................................. 219
Enabling Additional Paths...........................................................................................................220
Configuring IP Community Lists................................................................................................ 220
Configuring an IP Extended Community List............................................................................ 222
Filtering Routes with Community Lists...................................................................................... 223
Manipulating the COMMUNITY Attribute...................................................................................223
Changing MED Attributes........................................................................................................... 225
Changing the LOCAL_PREFERENCE Attribute.......................................................................... 225
Changing the NEXT_HOP Attribute........................................................................................... 226
Changing the WEIGHT Attribute.................................................................................................227
Enabling Multipath.......................................................................................................................227
Filtering BGP Routes................................................................................................................... 227
Filtering BGP Routes Using Route Maps.................................................................................... 229
Filtering BGP Routes Using AS-PATH Information....................................................................230
Configuring BGP Route Reflectors............................................................................................ 230
Aggregating Routes.....................................................................................................................231
Configuring BGP Confederations...............................................................................................232
Enabling Route Flap Dampening................................................................................................232
Changing BGP Timers.................................................................................................................235
Enabling BGP Neighbor Soft-Reconfiguration.......................................................................... 235
Route Map Continue...................................................................................................................237