Concept Guide

Congure BFD for IPv6 Static Routes....................................................................................................................151
Congure BFD for OSPF.........................................................................................................................................153
Congure BFD for OSPFv3.....................................................................................................................................156
Congure BFD for IS-IS...........................................................................................................................................159
Congure BFD for BGP............................................................................................................................................161
Congure BFD for VRRP.........................................................................................................................................169
Conguring Protocol Liveness.................................................................................................................................171
9 Border Gateway Protocol (BGP).................................................................................................................172
BGP IP version 4 (BGPv4) Overview.......................................................................................................................... 172
BGP Autonomous Systems........................................................................................................................................... 173
AS4 Number Representation...................................................................................................................................174
Four-Byte AS Numbers............................................................................................................................................176
Multiprotocol BGP..........................................................................................................................................................176
Sessions and Peers.........................................................................................................................................................177
Establish a Session....................................................................................................................................................177
BGP global and address family conguration..............................................................................................................178
BGP global conguration default values................................................................................................................ 178
BGP Attributes for selecting Best Path.......................................................................................................................179
Best Path Selection Criteria.................................................................................................................................... 179
Weight.........................................................................................................................................................................181
Local Preference........................................................................................................................................................181
Multi-Exit Discriminators (MEDs)...........................................................................................................................182
Origin..........................................................................................................................................................................183
AS Path......................................................................................................................................................................184
Next Hop................................................................................................................................................................... 184
Implement BGP with Dell EMC Networking OS.........................................................................................................185
Additional Path (Add-Path) Support......................................................................................................................185
Advertise IGP Cost as MED for Redistributed Routes........................................................................................ 185
Ignore Router-ID in Best-Path Calculation............................................................................................................ 186
AS Number Migration.............................................................................................................................................. 186
BGP4 Management Information Base (MIB)........................................................................................................187
Important Points to Remember...............................................................................................................................187
Conguration Information..............................................................................................................................................188
Basic BGP conguration tasks......................................................................................................................................188
Enabling BGP............................................................................................................................................................ 188
Conguring a BGP peer........................................................................................................................................... 191
Conguring AS4 Number Representations........................................................................................................... 192
Conguring a BGP VRF address family................................................................................................................. 193
Route-refresh and Soft-reconguration................................................................................................................195
Aggregating Routes..................................................................................................................................................198
Filtering BGP Routes................................................................................................................................................198
Filtering BGP Routes Using Route Maps...............................................................................................................198
Filtering BGP Routes Using AS-PATH Information.............................................................................................. 199
Conguring Peer Groups........................................................................................................................................ 200
Conguring BGP Fast Fall-Over............................................................................................................................ 208
Contents
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