Install Guide

Table Of Contents
Prerequisite for configuring a BGP network........................................................................................................181
Restrictions.................................................................................................................................................................. 181
Enabling BGP............................................................................................................................................................... 181
Enabling four-byte autonomous system numbers............................................................................................. 183
Changing a BGP router ID....................................................................................................................................... 184
Configuring AS4 Number Representations..........................................................................................................184
Configuring a BGP peer........................................................................................................................................... 185
Example-Configuring BGP routing between peers............................................................................................186
BGP peer group..........................................................................................................................................................187
Advanced BGP configuration tasks.............................................................................................................................194
Route-refresh and Soft-reconfiguration.............................................................................................................. 194
Aggregating Routes...................................................................................................................................................196
Filtering BGP...............................................................................................................................................................198
Configuring BGP Fast Fall-Over............................................................................................................................203
Configuring Passive Peering.................................................................................................................................. 205
Enabling Graceful Restart.......................................................................................................................................205
Redistributing Routes.............................................................................................................................................. 206
Redistributing iBGP Routes into IGP....................................................................................................................207
Enabling Additional Paths........................................................................................................................................209
Configuring IP Community Lists.............................................................................................................................210
Configuring an IP Extended Community List....................................................................................................... 211
Configure BGP attributes........................................................................................................................................ 212
Enabling Multipath.....................................................................................................................................................215
Route Reflectors........................................................................................................................................................216
Enabling Route Flap Dampening............................................................................................................................. 217
Changing BGP keepalive and hold timers............................................................................................................ 219
Setting the extended timer.....................................................................................................................................220
Enabling or disabling BGP neighbors....................................................................................................................220
Route Map Continue................................................................................................................................................. 221
Configuring BGP Confederations..........................................................................................................................222
Configuring a BGP VRF address family............................................................................................................... 222
Maintaining Existing AS Numbers During an AS Migration.............................................................................224
Allowing an AS Number to Appear in its Own AS Path................................................................................... 224
Enabling MBGP Configurations............................................................................................................................. 225
MBGP support for IPv6...........................................................................................................................................226
Configuring IPv6 MBGP between peers............................................................................................................. 226
Example-Configuring IPv4 and IPv6 neighbors................................................................................................. 226
Configure IPv6 NH Automatically for IPv6 Prefix Advertised over IPv4 Neighbor.................................. 229
BGP Regular Expression Optimization.................................................................................................................230
Debugging BGP......................................................................................................................................................... 230
Chapter 10: Content Addressable Memory (CAM)......................................................................233
CAM Allocation................................................................................................................................................................ 233
Test CAM Usage............................................................................................................................................................. 235
View CAM-ACL Settings...............................................................................................................................................235
View CAM Usage.............................................................................................................................................................237
Configuring CAM Threshold and Silence Period......................................................................................................237
CAM Optimization...........................................................................................................................................................239
Troubleshoot CAM Profiling......................................................................................................................................... 239
QoS CAM Region Limitation...................................................................................................................................239
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