Administrator Guide

AS Number Migration.....................................................................................................................................................176
BGP4 Management Information Base (MIB).............................................................................................................. 177
Important Points to Remember.............................................................................................................................. 178
Conguration Information..............................................................................................................................................178
BGP Conguration....................................................................................................................................................179
Enabling BGP.................................................................................................................................................................. 180
Conguring AS4 Number Representations................................................................................................................. 183
Conguring Peer Groups............................................................................................................................................... 184
Conguring BGP Fast Fall-Over................................................................................................................................... 187
Conguring Passive Peering......................................................................................................................................... 188
Maintaining Existing AS Numbers During an AS Migration....................................................................................... 189
Allowing an AS Number to Appear in its Own AS Path............................................................................................. 190
Enabling Graceful Restart............................................................................................................................................. 190
Enabling Neighbor Graceful Restart............................................................................................................................. 191
Filtering on an AS-Path Attribute................................................................................................................................. 192
Regular Expressions as Filters.................................................................................................................................193
Filtering BGP Routes Using AS-PATH Information.................................................................................................... 194
Redistributing Routes.................................................................................................................................................... 195
Enabling Additional Paths.............................................................................................................................................. 196
Conguring IP Community Lists................................................................................................................................... 196
Filtering Routes with Community Lists........................................................................................................................ 197
Manipulating the COMMUNITY Attribute...................................................................................................................198
Changing MED Attributes............................................................................................................................................. 199
Changing the LOCAL_PREFERENCE Attribute........................................................................................................ 199
Conguring the local System or a Dierent System to be the Next Hop for BGP-Learned Routes.................. 200
Changing the WEIGHT Attribute..................................................................................................................................201
Enabling Multipath..........................................................................................................................................................201
Filtering BGP Routes Using Route Maps.....................................................................................................................201
Filtering BGP Routes Using AS-PATH Information....................................................................................................202
Filtering BGP Routes.....................................................................................................................................................203
Filtering BGP Routes Using Route Maps..............................................................................................................204
Filtering BGP Routes Using AS-PATH Information............................................................................................. 205
Conguring BGP Route Reectors............................................................................................................................. 205
Aggregating Routes.......................................................................................................................................................206
Conguring BGP Confederations................................................................................................................................ 206
Enabling Route Flap Dampening.................................................................................................................................. 207
Changing BGP Timers...................................................................................................................................................209
Enabling BGP Neighbor Soft-Reconguration........................................................................................................... 210
Enabling or disabling BGP neighbors............................................................................................................................ 211
Route Map Continue......................................................................................................................................................212
Match a Clause with a Continue Clause................................................................................................................212
Set a Clause with a Continue Clause..................................................................................................................... 212
Enabling MBGP Congurations.................................................................................................................................... 212
Congure IPv6 NH Automatically for IPv6 Prex Advertised over IPv4 Neighbor.......................................... 213
BGP Regular Expression Optimization.........................................................................................................................213
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