Four-Byte AS Numbers............................................................................................................................................170
Multiprotocol BGP..........................................................................................................................................................170
Sessions and Peers......................................................................................................................................................... 171
Establish a Session....................................................................................................................................................171
BGP global and address family conguration..............................................................................................................172
BGP global conguration default values................................................................................................................ 172
BGP Attributes for selecting Best Path.......................................................................................................................173
Best Path Selection Criteria.................................................................................................................................... 173
Weight........................................................................................................................................................................175
Local Preference....................................................................................................................................................... 175
Multi-Exit Discriminators (MEDs)...........................................................................................................................176
Origin.......................................................................................................................................................................... 177
AS Path...................................................................................................................................................................... 178
Next Hop................................................................................................................................................................... 178
Implement BGP with Dell EMC Networking OS.........................................................................................................179
Additional Path (Add-Path) Support......................................................................................................................179
Advertise IGP Cost as MED for Redistributed Routes........................................................................................ 179
Ignore Router-ID in Best-Path Calculation............................................................................................................ 180
AS Number Migration.............................................................................................................................................. 180
BGP4 Management Information Base (MIB).........................................................................................................181
Important Points to Remember...............................................................................................................................181
Conguration Information..............................................................................................................................................182
Basic BGP conguration tasks......................................................................................................................................182
Enabling BGP............................................................................................................................................................ 182
Conguring a BGP peer...........................................................................................................................................185
Conguring AS4 Number Representations........................................................................................................... 186
Conguring a BGP VRF address family..................................................................................................................187
Route-refresh and Soft-reconguration................................................................................................................189
Aggregating Routes..................................................................................................................................................192
Filtering BGP Routes................................................................................................................................................192
Filtering BGP Routes Using Route Maps...............................................................................................................192
Filtering BGP Routes Using AS-PATH Information.............................................................................................. 193
Conguring Peer Groups.........................................................................................................................................194
Conguring BGP Fast Fall-Over............................................................................................................................ 202
Conguring Passive Peering...................................................................................................................................203
Maintaining Existing AS Numbers During an AS Migration................................................................................ 204
Allowing an AS Number to Appear in its Own AS Path...................................................................................... 205
Enabling Graceful Restart.......................................................................................................................................206
Filtering on an AS-Path Attribute...........................................................................................................................207
Regular Expressions as Filters................................................................................................................................208
Redistributing Routes..............................................................................................................................................209
Enabling Additional Paths........................................................................................................................................ 210
Conguring IP Community Lists..............................................................................................................................211
Conguring an IP Extended Community List........................................................................................................ 212
Filtering Routes with Community Lists.................................................................................................................. 213
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