Concept Guide

BGP global conguration default values.................................................................................................................171
BGP Attributes for selecting Best Path........................................................................................................................171
Best Path Selection Criteria.................................................................................................................................... 172
Weight........................................................................................................................................................................173
Local Preference....................................................................................................................................................... 174
Multi-Exit Discriminators (MEDs)........................................................................................................................... 174
Origin..........................................................................................................................................................................175
AS Path......................................................................................................................................................................176
Next Hop................................................................................................................................................................... 176
Implement BGP with Dell EMC Networking OS......................................................................................................... 177
Additional Path (Add-Path) Support...................................................................................................................... 177
Advertise IGP Cost as MED for Redistributed Routes.........................................................................................177
Ignore Router-ID in Best-Path Calculation............................................................................................................ 178
AS Number Migration...............................................................................................................................................178
BGP4 Management Information Base (MIB)........................................................................................................179
Important Points to Remember.............................................................................................................................. 179
Conguration Information..............................................................................................................................................180
Conguring a basic BGP network................................................................................................................................ 180
Enabling BGP............................................................................................................................................................ 180
Conguring a BGP peer...........................................................................................................................................183
Conguring AS4 Number Representations........................................................................................................... 184
Conguring a BGP VRF address family.................................................................................................................185
Route-refresh and Soft-reconguration................................................................................................................ 187
Aggregating Routes................................................................................................................................................. 190
Filtering BGP Routes................................................................................................................................................190
Filtering BGP Routes Using Route Maps...............................................................................................................192
Filtering BGP Routes Using AS-PATH Information.............................................................................................. 192
Conguring Peer Groups.........................................................................................................................................193
Conguring BGP Fast Fall-Over.............................................................................................................................201
Conguring Passive Peering...................................................................................................................................202
Maintaining Existing AS Numbers During an AS Migration................................................................................ 203
Allowing an AS Number to Appear in its Own AS Path...................................................................................... 204
Enabling Graceful Restart.......................................................................................................................................205
Filtering on an AS-Path Attribute.......................................................................................................................... 206
Regular Expressions as Filters................................................................................................................................ 207
Redistributing Routes..............................................................................................................................................208
Enabling Additional Paths....................................................................................................................................... 209
Redistributing iBGP Routes into IGP.....................................................................................................................209
Conguring IP Community Lists..............................................................................................................................211
Conguring an IP Extended Community List........................................................................................................ 213
Filtering Routes with Community Lists.................................................................................................................. 213
Manipulating the COMMUNITY Attribute.............................................................................................................214
Changing MED Attributes....................................................................................................................................... 215
Changing the LOCAL_PREFERENCE Attribute.................................................................................................. 216
Conguring the local System or a Dierent System to be the Next Hop for BGP-Learned Routes............. 217
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