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Multi-Exit Discriminators (MEDs)...........................................................................................................................166
Origin..........................................................................................................................................................................167
AS Path......................................................................................................................................................................168
Next Hop................................................................................................................................................................... 168
Multiprotocol BGP..........................................................................................................................................................168
Implement BGP with Dell EMC Networking OS.........................................................................................................169
Additional Path (Add-Path) Support......................................................................................................................169
Advertise IGP Cost as MED for Redistributed Routes........................................................................................ 169
Ignore Router-ID in Best-Path Calculation............................................................................................................ 170
Four-Byte AS Numbers............................................................................................................................................170
AS4 Number Representation.................................................................................................................................. 170
AS Number Migration...............................................................................................................................................172
BGP4 Management Information Base (MIB)........................................................................................................173
Important Points to Remember.............................................................................................................................. 173
Conguration Information..............................................................................................................................................174
BGP Conguration..........................................................................................................................................................174
Enabling BGP............................................................................................................................................................ 175
Conguring AS4 Number Representations........................................................................................................... 178
Conguring Peer Groups.........................................................................................................................................180
Conguring BGP Fast Fall-Over............................................................................................................................. 182
Conguring Passive Peering................................................................................................................................... 184
Maintaining Existing AS Numbers During an AS Migration................................................................................. 184
Allowing an AS Number to Appear in its Own AS Path.......................................................................................185
Enabling Graceful Restart........................................................................................................................................186
Enabling Neighbor Graceful Restart.......................................................................................................................187
Filtering on an AS-Path Attribute............................................................................................................................187
Regular Expressions as Filters.................................................................................................................................189
Redistributing Routes.............................................................................................................................................. 190
Enabling Additional Paths.........................................................................................................................................191
Conguring IP Community Lists..............................................................................................................................191
Conguring an IP Extended Community List........................................................................................................192
Filtering Routes with Community Lists..................................................................................................................193
Manipulating the COMMUNITY Attribute.............................................................................................................194
Changing MED Attributes....................................................................................................................................... 195
Changing the LOCAL_PREFERENCE Attribute.................................................................................................. 195
Conguring the local System or a Dierent System to be the Next Hop for BGP-Learned Routes............. 196
Changing the WEIGHT Attribute............................................................................................................................197
Enabling Multipath....................................................................................................................................................197
Filtering BGP Routes................................................................................................................................................197
Filtering BGP Routes Using Route Maps.............................................................................................................. 199
Filtering BGP Routes Using AS-PATH Information.............................................................................................. 199
Conguring BGP Route Reectors....................................................................................................................... 200
Aggregating Routes..................................................................................................................................................201
Conguring BGP Confederations........................................................................................................................... 201
Enabling Route Flap Dampening............................................................................................................................ 202
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