Concept Guide

Allowing an AS Number to Appear in its Own AS Path...................................................................................... 202
Enabling Graceful Restart.......................................................................................................................................203
Enabling Neighbor Graceful Restart......................................................................................................................204
Filtering on an AS-Path Attribute.......................................................................................................................... 204
Regular Expressions as Filters................................................................................................................................206
Redistributing Routes.............................................................................................................................................. 207
Enabling Additional Paths....................................................................................................................................... 208
Conguring IP Community Lists............................................................................................................................ 208
Conguring an IP Extended Community List....................................................................................................... 209
Filtering Routes with Community Lists..................................................................................................................210
Manipulating the COMMUNITY Attribute..............................................................................................................211
Changing MED Attributes....................................................................................................................................... 212
Changing the LOCAL_PREFERENCE Attribute...................................................................................................212
Conguring the local System or a Dierent System to be the Next Hop for BGP-Learned Routes............. 213
Changing the WEIGHT Attribute............................................................................................................................214
Enabling Multipath....................................................................................................................................................214
Filtering BGP Routes................................................................................................................................................214
Filtering BGP Routes Using Route Maps...............................................................................................................216
Filtering BGP Routes Using AS-PATH Information.............................................................................................. 216
Conguring BGP Route Reectors.........................................................................................................................217
Aggregating Routes..................................................................................................................................................218
Conguring BGP Confederations........................................................................................................................... 218
Enabling Route Flap Dampening.............................................................................................................................219
Changing BGP Timers..............................................................................................................................................221
Route-refresh and Soft-reconguration................................................................................................................221
Enabling or disabling BGP neighbors.....................................................................................................................223
Route Map Continue............................................................................................................................................... 224
Enabling MBGP Congurations....................................................................................................................................224
Congure IPv6 NH Automatically for IPv6 Prex Advertised over IPv4 Neighbor......................................... 225
BGP Regular Expression Optimization........................................................................................................................ 227
Debugging BGP..............................................................................................................................................................227
Storing Last and Bad PDUs....................................................................................................................................228
Capturing PDUs....................................................................................................................................................... 229
PDU Counters.......................................................................................................................................................... 230
Example-Conguring BGP peer groups......................................................................................................................230
10 Content Addressable Memory (CAM).......................................................................................................237
CAM Allocation...............................................................................................................................................................237
Test CAM Usage............................................................................................................................................................239
View CAM Proles.........................................................................................................................................................239
View CAM-ACL Settings.............................................................................................................................................. 240
View CAM Usage............................................................................................................................................................241
Conguring CAM Threshold and Silence Period........................................................................................................242
Setting CAM Threshold and Silence Period..........................................................................................................242
CAM Optimization......................................................................................................................................................... 243
Troubleshoot CAM Proling..........................................................................................................................................243
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