Weight........................................................................................................................................................................159
Local Preference.......................................................................................................................................................159
Multi-Exit Discriminators (MEDs)...........................................................................................................................160
Origin.......................................................................................................................................................................... 161
AS Path.......................................................................................................................................................................161
Next Hop................................................................................................................................................................... 162
Multiprotocol BGP..........................................................................................................................................................162
Implement BGP with Dell Networking OS...................................................................................................................163
Additional Path (Add-Path) Support......................................................................................................................163
Advertise IGP Cost as MED for Redistributed Routes........................................................................................ 163
Ignore Router-ID in Best-Path Calculation............................................................................................................ 164
Four-Byte AS Numbers............................................................................................................................................164
AS4 Number Representation.................................................................................................................................. 164
AS Number Migration.............................................................................................................................................. 166
BGP4 Management Information Base (MIB)........................................................................................................ 167
Important Points to Remember.............................................................................................................................. 167
Conguration Information..............................................................................................................................................168
BGP Conguration......................................................................................................................................................... 168
Enabling BGP............................................................................................................................................................ 169
Conguring AS4 Number Representations........................................................................................................... 172
Conguring Peer Groups......................................................................................................................................... 173
Conguring BGP Fast Fall-Over............................................................................................................................. 176
Conguring Passive Peering....................................................................................................................................177
Maintaining Existing AS Numbers During an AS Migration................................................................................. 178
Allowing an AS Number to Appear in its Own AS Path....................................................................................... 179
Enabling Graceful Restart....................................................................................................................................... 180
Enabling Neighbor Graceful Restart....................................................................................................................... 181
Filtering on an AS-Path Attribute............................................................................................................................181
Regular Expressions as Filters.................................................................................................................................182
Redistributing Routes...............................................................................................................................................184
Enabling Additional Paths........................................................................................................................................ 184
Conguring IP Community Lists............................................................................................................................. 185
Conguring an IP Extended Community List........................................................................................................186
Filtering Routes with Community Lists.................................................................................................................. 187
Manipulating the COMMUNITY Attribute............................................................................................................. 187
Changing MED Attributes....................................................................................................................................... 189
Changing the LOCAL_PREFERENCE Attribute.................................................................................................. 189
Changing the NEXT_HOP Attribute......................................................................................................................190
Changing the WEIGHT Attribute............................................................................................................................190
Enabling Multipath.................................................................................................................................................... 191
Filtering BGP Routes................................................................................................................................................ 191
Filtering BGP Routes Using Route Maps...............................................................................................................192
Filtering BGP Routes Using AS-PATH Information.............................................................................................. 193
Conguring BGP Route Reectors........................................................................................................................ 193
Aggregating Routes..................................................................................................................................................194
Conguring BGP Confederations...........................................................................................................................194
Enabling Route Flap Dampening.............................................................................................................................195
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