Users Guide

BGP4 Management Information Base (MIB)............................................................................................................ 185
Important Points to Remember.................................................................................................................................185
Conguration Information............................................................................................................................................... 186
BGP Conguration..........................................................................................................................................................186
Enabling BGP............................................................................................................................................................ 187
Conguring AS4 Number Representations................................................................................................................190
Conguring Peer Groups...........................................................................................................................................192
Conguring BGP Fast Fall-Over................................................................................................................................194
Conguring Passive Peering..................................................................................................................................... 196
Maintaining Existing AS Numbers During an AS Migration........................................................................................ 196
Allowing an AS Number to Appear in its Own AS Path..............................................................................................197
Enabling Graceful Restart......................................................................................................................................... 198
Enabling Neighbor Graceful Restart..........................................................................................................................199
Filtering on an AS-Path Attribute..............................................................................................................................199
Regular Expressions as Filters................................................................................................................................... 201
Redistributing Routes...............................................................................................................................................202
Enabling Additional Paths......................................................................................................................................... 203
Conguring IP Community Lists............................................................................................................................... 203
Conguring an IP Extended Community List............................................................................................................204
Filtering Routes with Community Lists.....................................................................................................................205
Manipulating the COMMUNITY Attribute................................................................................................................ 205
Changing MED Attributes.........................................................................................................................................207
Changing the LOCAL_PREFERENCE Attribute....................................................................................................... 207
Changing the NEXT_HOP Attribute.........................................................................................................................208
Changing the WEIGHT Attribute..............................................................................................................................208
Enabling Multipath................................................................................................................................................... 209
Filtering BGP Routes................................................................................................................................................209
Filtering BGP Routes Using Route Maps...................................................................................................................210
Filtering BGP Routes Using AS-PATH Information.....................................................................................................211
Conguring BGP Route Reectors............................................................................................................................ 211
Aggregating Routes.................................................................................................................................................. 212
Conguring BGP Confederations.............................................................................................................................. 212
Enabling Route Flap Dampening................................................................................................................................213
Changing BGP Timers...............................................................................................................................................215
Enabling BGP Neighbor Soft-Reconguration...........................................................................................................216
Route Map Continue.................................................................................................................................................217
Enabling MBGP Congurations.......................................................................................................................................217
BGP Regular Expression Optimization.............................................................................................................................218
Debugging BGP.............................................................................................................................................................. 218
Storing Last and Bad PDUs.......................................................................................................................................219
Capturing PDUs....................................................................................................................................................... 220
PDU Counters...........................................................................................................................................................221
Sample Congurations....................................................................................................................................................221
11 Content Addressable Memory (CAM).........................................................................228
CAM Allocation.............................................................................................................................................................. 228
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