Concept Guide

BFD Three-Way Handshake.................................................................................................................................... 147
Session State Changes............................................................................................................................................149
Important Points to Remember.................................................................................................................................... 149
Congure BFD................................................................................................................................................................ 149
Congure BFD for Physical Ports.......................................................................................................................... 150
Congure BFD for Static Routes.............................................................................................................................151
Congure BFD for OSPF.........................................................................................................................................154
Congure BFD for OSPFv3.....................................................................................................................................158
Congure BFD for IS-IS............................................................................................................................................161
Congure BFD for BGP........................................................................................................................................... 163
Congure BFD for VRRP..........................................................................................................................................171
Conguring Protocol Liveness.................................................................................................................................174
Troubleshooting BFD................................................................................................................................................ 174
9 Border Gateway Protocol version 4 (BGPv4)..............................................................................................176
Autonomous Systems (AS)........................................................................................................................................... 176
Sessions and Peers.........................................................................................................................................................178
Establish a Session................................................................................................................................................... 178
Route Reectors.............................................................................................................................................................179
BGP Attributes for selecting Best Path.......................................................................................................................180
Best Path Selection Criteria....................................................................................................................................180
Weight........................................................................................................................................................................182
Local Preference.......................................................................................................................................................182
Multi-Exit Discriminators (MEDs)...........................................................................................................................183
Origin..........................................................................................................................................................................184
AS Path......................................................................................................................................................................185
Next Hop................................................................................................................................................................... 185
Multiprotocol BGP..........................................................................................................................................................185
MBGP for IPv4 MulticastBGP Address Family modelIPv4 and IPv6 address family....................................... 186
Implement BGP with Dell EMC Networking OS.........................................................................................................186
Additional Path (Add-Path) Support......................................................................................................................186
Advertise IGP Cost as MED for Redistributed Routes.........................................................................................187
Ignore Router-ID in Best-Path Calculation.............................................................................................................187
Four-Byte AS Numbers............................................................................................................................................187
AS4 Number Representation.................................................................................................................................. 188
AS Number Migration.............................................................................................................................................. 189
BGP4 Management Information Base (MIB)........................................................................................................190
Important Points to Remember..............................................................................................................................190
Conguration Information.............................................................................................................................................. 191
Enabling BGP.................................................................................................................................................................. 192
Enabling BGP............................................................................................................................................................ 193
Conguring AS4 Number Representations...........................................................................................................195
Conguring Peer Groups......................................................................................................................................... 197
Conguring BGP Fast Fall-Over.............................................................................................................................199
Conguring Passive Peering...................................................................................................................................200
Maintaining Existing AS Numbers During an AS Migration.................................................................................201
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