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AS Number Migration.....................................................................................................................................................178
BGP4 Management Information Base (MIB)..............................................................................................................179
Important Points to Remember..............................................................................................................................180
Conguration Information..............................................................................................................................................180
BGP Conguration.................................................................................................................................................... 181
Enabling BGP.................................................................................................................................................................. 182
Conguring AS4 Number Representations.................................................................................................................185
Conguring Peer Groups...............................................................................................................................................186
Conguring BGP Fast Fall-Over...................................................................................................................................189
Conguring Passive Peering......................................................................................................................................... 190
Maintaining Existing AS Numbers During an AS Migration........................................................................................191
Allowing an AS Number to Appear in its Own AS Path............................................................................................. 192
Enabling Graceful Restart..............................................................................................................................................192
Enabling Neighbor Graceful Restart.............................................................................................................................193
Filtering on an AS-Path Attribute................................................................................................................................. 194
Regular Expressions as Filters.................................................................................................................................195
Filtering BGP Routes Using AS-PATH Information.................................................................................................... 196
Redistributing Routes.....................................................................................................................................................197
Enabling Additional Paths.............................................................................................................................................. 198
Conguring IP Community Lists................................................................................................................................... 198
Filtering Routes with Community Lists........................................................................................................................199
Manipulating the COMMUNITY Attribute..................................................................................................................200
Changing MED Attributes............................................................................................................................................. 201
Changing the LOCAL_PREFERENCE Attribute........................................................................................................ 201
Conguring the local System or a Dierent System to be the Next Hop for BGP-Learned Routes.................. 202
Changing the WEIGHT Attribute.................................................................................................................................203
Enabling Multipath.........................................................................................................................................................203
Filtering BGP Routes Using Route Maps....................................................................................................................203
Filtering BGP Routes Using AS-PATH Information................................................................................................... 204
Filtering BGP Routes.....................................................................................................................................................205
Filtering BGP Routes Using Route Maps..............................................................................................................206
Filtering BGP Routes Using AS-PATH Information..............................................................................................207
Conguring BGP Route Reectors..............................................................................................................................207
Aggregating Routes.......................................................................................................................................................208
Conguring BGP Confederations................................................................................................................................ 208
Enabling Route Flap Dampening.................................................................................................................................. 209
Changing BGP Timers.................................................................................................................................................... 211
Enabling BGP Neighbor Soft-Reconguration............................................................................................................212
Enabling or disabling BGP neighbors............................................................................................................................213
Route Map Continue......................................................................................................................................................214
Match a Clause with a Continue Clause................................................................................................................214
Set a Clause with a Continue Clause..................................................................................................................... 214
Enabling MBGP Congurations.................................................................................................................................... 214
Congure IPv6 NH Automatically for IPv6 Prex Advertised over IPv4 Neighbor..........................................215
BGP Regular Expression Optimization.........................................................................................................................215
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