Setup Guide

Congure BFD for BGP........................................................................................................................................... 157
Congure BFD for VRRP.........................................................................................................................................164
Conguring Protocol Liveness................................................................................................................................ 167
9 Border Gateway Protocol IPv4 (BGPv4).................................................................................................... 168
Autonomous Systems (AS)........................................................................................................................................... 168
Sessions and Peers.........................................................................................................................................................170
Establish a Session................................................................................................................................................... 170
Route Reectors..............................................................................................................................................................171
BGP Attributes................................................................................................................................................................172
Best Path Selection Criteria.................................................................................................................................... 172
Weight........................................................................................................................................................................ 174
Local Preference....................................................................................................................................................... 174
Multi-Exit Discriminators (MEDs)...........................................................................................................................175
Origin..........................................................................................................................................................................176
AS Path...................................................................................................................................................................... 177
Next Hop....................................................................................................................................................................177
Multiprotocol BGP.......................................................................................................................................................... 177
Implement BGP with Dell EMC Networking OS......................................................................................................... 178
Additional Path (Add-Path) Support...................................................................................................................... 178
Advertise IGP Cost as MED for Redistributed Routes.........................................................................................178
Ignore Router-ID in Best-Path Calculation............................................................................................................ 179
Four-Byte AS Numbers............................................................................................................................................179
AS4 Number Representation.................................................................................................................................. 179
AS Number Migration............................................................................................................................................... 181
BGP4 Management Information Base (MIB)........................................................................................................182
Important Points to Remember.............................................................................................................................. 182
Conguration Information..............................................................................................................................................183
BGP Conguration......................................................................................................................................................... 183
Enabling BGP............................................................................................................................................................ 184
Conguring AS4 Number Representations........................................................................................................... 187
Conguring Peer Groups.........................................................................................................................................189
Conguring BGP Fast Fall-Over..............................................................................................................................191
Conguring Passive Peering................................................................................................................................... 193
Maintaining Existing AS Numbers During an AS Migration................................................................................. 193
Allowing an AS Number to Appear in its Own AS Path....................................................................................... 194
Enabling Graceful Restart....................................................................................................................................... 195
Enabling Neighbor Graceful Restart...................................................................................................................... 196
Filtering on an AS-Path Attribute........................................................................................................................... 196
Regular Expressions as Filters.................................................................................................................................198
Redistributing Routes.............................................................................................................................................. 199
Enabling Additional Paths....................................................................................................................................... 200
Conguring IP Community Lists............................................................................................................................ 200
Conguring an IP Extended Community List........................................................................................................201
Filtering Routes with Community Lists................................................................................................................. 202
Manipulating the COMMUNITY Attribute............................................................................................................ 203
Contents
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