Concept Guide

Congure BFD for IS-IS...........................................................................................................................................158
Congure BFD for BGP...........................................................................................................................................160
Congure BFD for VRRP.........................................................................................................................................168
Conguring Protocol Liveness................................................................................................................................ 170
9 Border Gateway Protocol (BGP)................................................................................................................. 171
Border Gateway Protocol version 4 (BGPv4)..............................................................................................................171
Autonomous Systems (AS)............................................................................................................................................171
AS4 Number Representation.................................................................................................................................. 173
Four-Byte AS Numbers............................................................................................................................................175
Multiprotocol BGP..........................................................................................................................................................175
MBGP for IPv4 MulticastBGP Address Family modelIPv4 and IPv6 address family....................................... 176
Sessions and Peers.........................................................................................................................................................176
Establish a Session................................................................................................................................................... 176
Implementing BGP global and address family..............................................................................................................177
BGP global conguration default values................................................................................................................ 178
BGP Attributes for selecting Best Path.......................................................................................................................178
Best Path Selection Criteria.................................................................................................................................... 179
Weight........................................................................................................................................................................180
Local Preference........................................................................................................................................................181
Multi-Exit Discriminators (MEDs)........................................................................................................................... 181
Origin..........................................................................................................................................................................182
AS Path......................................................................................................................................................................183
Next Hop................................................................................................................................................................... 183
Implement BGP with Dell EMC Networking OS.........................................................................................................184
Additional Path (Add-Path) Support......................................................................................................................184
Advertise IGP Cost as MED for Redistributed Routes........................................................................................ 184
Ignore Router-ID in Best-Path Calculation............................................................................................................ 185
AS Number Migration.............................................................................................................................................. 185
BGP4 Management Information Base (MIB)........................................................................................................186
Important Points to Remember.............................................................................................................................. 186
Conguration Information..............................................................................................................................................187
Conguring a basic BGP network.................................................................................................................................187
Enabling BGP.............................................................................................................................................................187
Conguring a BGP peer...........................................................................................................................................190
Conguring AS4 Number Representations............................................................................................................191
Conguring a BGP VRF address family................................................................................................................. 192
Route-refresh and Soft-reconguration................................................................................................................194
Aggregating Routes..................................................................................................................................................197
Filtering BGP Routes................................................................................................................................................197
Filtering BGP Routes Using Route Maps.............................................................................................................. 199
Filtering BGP Routes Using AS-PATH Information.............................................................................................. 199
Conguring Peer Groups........................................................................................................................................ 200
Conguring BGP Fast Fall-Over............................................................................................................................ 208
Conguring Passive Peering...................................................................................................................................209
Maintaining Existing AS Numbers During an AS Migration.................................................................................210
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