Administrator Guide

Prerequisite for configuring a BGP network.............................................................................................................174
Restrictions................................................................................................................................................................... 174
Enabling BGP................................................................................................................................................................ 174
Enabling four-byte autonomous system numbers................................................................................................... 176
Changing a BGP router ID...........................................................................................................................................177
Configuring AS4 Number Representations............................................................................................................... 177
Configuring a BGP peer...............................................................................................................................................178
Example-Configuring BGP routing between peers..................................................................................................179
BGP peer group............................................................................................................................................................180
Advanced BGP configuration tasks................................................................................................................................. 187
Route-refresh and Soft-reconfiguration................................................................................................................... 187
Aggregating Routes..................................................................................................................................................... 189
Filtering BGP..................................................................................................................................................................191
Configuring BGP Fast Fall-Over.................................................................................................................................196
Configuring Passive Peering....................................................................................................................................... 197
Enabling Graceful Restart........................................................................................................................................... 198
Redistributing Routes.................................................................................................................................................. 199
Redistributing iBGP Routes into IGP......................................................................................................................... 199
Enabling Additional Paths........................................................................................................................................... 202
Configuring IP Community Lists................................................................................................................................202
Configuring an IP Extended Community List...........................................................................................................203
Configure BGP attributes...........................................................................................................................................204
Enabling Multipath.......................................................................................................................................................207
Route Reflectors......................................................................................................................................................... 208
Enabling Route Flap Dampening................................................................................................................................209
Changing BGP keepalive and hold timers.................................................................................................................. 211
Setting the extended timer.........................................................................................................................................212
Enabling or disabling BGP neighbors......................................................................................................................... 212
Route Map Continue....................................................................................................................................................213
Configuring BGP Confederations...............................................................................................................................214
Configuring a BGP VRF address family.....................................................................................................................214
Maintaining Existing AS Numbers During an AS Migration.....................................................................................215
Allowing an AS Number to Appear in its Own AS Path...........................................................................................216
Enabling MBGP Configurations.................................................................................................................................. 217
MBGP support for IPv6...............................................................................................................................................217
Configuring IPv6 MBGP between peers................................................................................................................... 217
Example-Configuring IPv4 and IPv6 neighbors........................................................................................................218
Configure IPv6 NH Automatically for IPv6 Prefix Advertised over IPv4 Neighbor............................................ 220
BGP Regular Expression Optimization......................................................................................................................222
Debugging BGP........................................................................................................................................................... 222
10 Content Addressable Memory (CAM)........................................................................................224
CAM Allocation.................................................................................................................................................................. 224
Test CAM Usage...............................................................................................................................................................225
View CAM-ACL Settings..................................................................................................................................................226
View CAM Usage...............................................................................................................................................................227
Configuring CAM Threshold and Silence Period........................................................................................................... 228
CAM Optimization.............................................................................................................................................................229
Troubleshoot CAM Profiling.............................................................................................................................................229
QoS CAM Region Limitation...................................................................................................................................... 229
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