Connectivity Guide

Table Of Contents
Prerequisite for configuring a BGP network....................................................................................................... 177
Restrictions..................................................................................................................................................................177
Enabling BGP...............................................................................................................................................................177
Enabling four-byte autonomous system numbers..............................................................................................179
Changing a BGP router ID....................................................................................................................................... 180
Configuring AS4 Number Representations..........................................................................................................180
Configuring a BGP peer............................................................................................................................................ 181
Example-Configuring BGP routing between peers............................................................................................182
BGP peer group..........................................................................................................................................................183
Advanced BGP configuration tasks............................................................................................................................ 190
Route-refresh and Soft-reconfiguration..............................................................................................................190
Aggregating Routes...................................................................................................................................................192
Filtering BGP...............................................................................................................................................................194
Configuring BGP Fast Fall-Over.............................................................................................................................199
Configuring Passive Peering................................................................................................................................... 201
Enabling Graceful Restart........................................................................................................................................201
Redistributing Routes...............................................................................................................................................202
Redistributing iBGP Routes into IGP....................................................................................................................203
Enabling Additional Paths........................................................................................................................................205
Configuring IP Community Lists............................................................................................................................206
Configuring an IP Extended Community List......................................................................................................207
Configure BGP attributes....................................................................................................................................... 208
Enabling Multipath......................................................................................................................................................211
Route Reflectors........................................................................................................................................................ 212
Enabling Route Flap Dampening.............................................................................................................................213
Changing BGP keepalive and hold timers............................................................................................................ 215
Setting the extended timer..................................................................................................................................... 216
Enabling or disabling BGP neighbors.....................................................................................................................216
Route Map Continue................................................................................................................................................. 217
Configuring BGP Confederations...........................................................................................................................218
Configuring a BGP VRF address family................................................................................................................ 218
Maintaining Existing AS Numbers During an AS Migration.............................................................................220
Allowing an AS Number to Appear in its Own AS Path................................................................................... 220
Enabling MBGP Configurations.............................................................................................................................. 221
MBGP support for IPv6...........................................................................................................................................222
Configuring IPv6 MBGP between peers..............................................................................................................222
Example-Configuring IPv4 and IPv6 neighbors..................................................................................................222
Configure IPv6 NH Automatically for IPv6 Prefix Advertised over IPv4 Neighbor...................................224
BGP Regular Expression Optimization.................................................................................................................226
Debugging BGP......................................................................................................................................................... 226
Chapter 10: Content Addressable Memory (CAM)......................................................................229
CAM Allocation................................................................................................................................................................ 229
Test CAM Usage..............................................................................................................................................................231
View CAM-ACL Settings................................................................................................................................................231
View CAM Usage............................................................................................................................................................ 233
Configuring CAM Threshold and Silence Period..................................................................................................... 233
CAM Optimization.......................................................................................................................................................... 235
Troubleshoot CAM Profiling.........................................................................................................................................235
QoS CAM Region Limitation...................................................................................................................................235
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