Local Preference.......................................................................................................................................................... 157
Multi-Exit Discriminators (MEDs).............................................................................................................................. 158
Origin............................................................................................................................................................................. 159
AS Path......................................................................................................................................................................... 159
Next Hop.......................................................................................................................................................................160
Multiprotocol BGP............................................................................................................................................................. 160
Implement BGP with Dell Networking OS...................................................................................................................... 160
Advertise IGP Cost as MED for Redistributed Routes............................................................................................ 161
Ignore Router-ID for Some Best-Path Calculations................................................................................................. 161
Four-Byte AS Numbers................................................................................................................................................161
AS4 Number Representation......................................................................................................................................162
AS Number Migration..................................................................................................................................................163
BGP4 Management Information Base (MIB)........................................................................................................... 164
Important Points to Remember..................................................................................................................................165
Configuration Information.................................................................................................................................................165
BGP Configuration.............................................................................................................................................................166
Enabling BGP................................................................................................................................................................166
Configuring AS4 Number Representations...............................................................................................................169
Configuring Peer Groups..............................................................................................................................................171
Configuring BGP Fast Fall-Over.................................................................................................................................173
Configuring Passive Peering....................................................................................................................................... 174
Maintaining Existing AS Numbers During an AS Migration.....................................................................................175
Allowing an AS Number to Appear in its Own AS Path...........................................................................................175
Enabling Graceful Restart........................................................................................................................................... 176
Enabling Neighbor Graceful Restart...........................................................................................................................177
Filtering on an AS-Path Attribute...............................................................................................................................177
Regular Expressions as Filters.................................................................................................................................... 178
Redistributing Routes.................................................................................................................................................. 180
Enabling Additional Paths............................................................................................................................................180
Configuring IP Community Lists..................................................................................................................................181
Configuring an IP Extended Community List............................................................................................................182
Filtering Routes with Community Lists......................................................................................................................182
Manipulating the COMMUNITY Attribute................................................................................................................ 183
Changing MED Attributes...........................................................................................................................................184
Changing the LOCAL_PREFERENCE Attribute......................................................................................................184
Changing the NEXT_HOP Attribute......................................................................................................................... 185
Changing the WEIGHT Attribute............................................................................................................................... 185
Enabling Multipath....................................................................................................................................................... 186
Filtering BGP Routes................................................................................................................................................... 186
Filtering BGP Routes Using Route Maps.................................................................................................................. 187
Filtering BGP Routes Using AS-PATH Information................................................................................................. 187
Configuring BGP Route Reflectors............................................................................................................................188
Aggregating Routes..................................................................................................................................................... 188
Configuring BGP Confederations...............................................................................................................................189
Enabling Route Flap Dampening.................................................................................................................................189
Changing BGP Timers.................................................................................................................................................. 191
Enabling BGP Neighbor Soft-Reconfiguration.........................................................................................................192
Route Map Continue....................................................................................................................................................193
Enabling MBGP Configurations........................................................................................................................................193
BGP Regular Expression Optimization............................................................................................................................ 194
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