Concept Guide

Conguring Passive Peering...................................................................................................................................202
Maintaining Existing AS Numbers During an AS Migration................................................................................ 203
Allowing an AS Number to Appear in its Own AS Path...................................................................................... 204
Enabling Graceful Restart.......................................................................................................................................205
Enabling Neighbor Graceful Restart......................................................................................................................206
Enabling or disabling BGP neighbors.....................................................................................................................206
Filtering on an AS-Path Attribute.......................................................................................................................... 208
Regular Expressions as Filters................................................................................................................................209
Redistributing Routes...............................................................................................................................................210
Enabling Additional Paths......................................................................................................................................... 211
Conguring IP Community Lists............................................................................................................................. 212
Conguring an IP Extended Community List........................................................................................................ 213
Filtering Routes with Community Lists.................................................................................................................. 214
Manipulating the COMMUNITY Attribute.............................................................................................................215
Changing MED Attributes....................................................................................................................................... 216
Changing the LOCAL_PREFERENCE Attribute...................................................................................................217
Conguring the local System or a Dierent System to be the Next Hop for BGP-Learned Routes............. 217
Changing the WEIGHT Attribute............................................................................................................................218
Enabling Multipath....................................................................................................................................................218
Filtering BGP Routes................................................................................................................................................219
Filtering BGP Routes Using Route Maps...............................................................................................................219
Filtering BGP Routes Using AS-PATH Information..............................................................................................220
Conguring BGP Route Reectors........................................................................................................................ 221
Aggregating Routes.................................................................................................................................................222
Conguring BGP Confederations.......................................................................................................................... 222
Enabling Route Flap Dampening............................................................................................................................ 223
Changing BGP keepalive and hold timers.............................................................................................................225
Route-refresh and Soft-reconguration............................................................................................................... 226
Enabling or disabling BGP neighbors.....................................................................................................................227
Route Map Continue............................................................................................................................................... 228
Enabling MBGP Congurations................................................................................................................................... 229
Congure IPv6 NH Automatically for IPv6 Prex Advertised over IPv4 Neighbor......................................... 229
BGP Regular Expression Optimization.........................................................................................................................231
Debugging BGP.............................................................................................................................................................. 231
Storing Last and Bad PDUs....................................................................................................................................232
Capturing PDUs....................................................................................................................................................... 233
PDU Counters.......................................................................................................................................................... 234
Example-Conguring BGP peer groups......................................................................................................................234
10 Content Addressable Memory (CAM)....................................................................................................... 241
CAM Allocation............................................................................................................................................................... 241
Test CAM Usage............................................................................................................................................................ 243
View CAM-ACL Settings.............................................................................................................................................. 243
View CAM Usage...........................................................................................................................................................245
Conguring CAM Threshold and Silence Period........................................................................................................245
Setting CAM Threshold and Silence Period......................................................................................................... 245
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