Service Manual

Guidelines for Configuring ACL Logging.....................................................................................................143
Configuring ACL Logging............................................................................................................................... 144
Flow-Based Monitoring Support for ACLs........................................................................................................144
Behavior of Flow-Based Monitoring.............................................................................................................145
Enabling Flow-Based Monitoring..................................................................................................................146
Configuring UDF ACL............................................................................................................................................ 147
9 Bidirectional Forwarding Detection (BFD)..................................................................................................... 150
How BFD Works......................................................................................................................................................150
BFD Packet Format........................................................................................................................................... 151
BFD Sessions......................................................................................................................................................152
BFD Three-Way Handshake........................................................................................................................... 153
Session State Changes.....................................................................................................................................155
Important Points to Remember...........................................................................................................................155
Configure BFD.........................................................................................................................................................155
Configure BFD for Physical Ports..................................................................................................................156
Configure BFD for Static Routes................................................................................................................... 159
Configure BFD for OSPF..................................................................................................................................161
Configure BFD for OSPFv3............................................................................................................................. 164
Configure BFD for IS-IS...................................................................................................................................165
Configure BFD for BGP....................................................................................................................................167
Configure BFD for VRRP..................................................................................................................................174
Configuring Protocol Liveness.......................................................................................................................176
Troubleshooting BFD.......................................................................................................................................176
10 Border Gateway Protocol IPv4 (BGPv4)....................................................................................................... 178
Autonomous Systems (AS)....................................................................................................................................178
Sessions and Peers.................................................................................................................................................180
Establish a Session............................................................................................................................................ 181
Route Reflectors......................................................................................................................................................181
BGP Attributes.........................................................................................................................................................182
Best Path Selection Criteria............................................................................................................................ 183
Weight................................................................................................................................................................. 185
Local Preference...............................................................................................................................................185
Multi-Exit Discriminators (MEDs)...................................................................................................................185
Origin...................................................................................................................................................................186
AS Path................................................................................................................................................................ 187
Next Hop.............................................................................................................................................................187
Multiprotocol BGP..................................................................................................................................................187
Implement BGP with Dell Networking OS........................................................................................................188
Additional Path (Add-Path) Support............................................................................................................. 188
Advertise IGP Cost as MED for Redistributed Routes............................................................................... 188
Ignore Router-ID in Best-Path Calculation................................................................................................ 189
Four-Byte AS Numbers....................................................................................................................................189
AS4 Number Representation..........................................................................................................................189
AS Number Migration.......................................................................................................................................191
BGP4 Management Information Base (MIB)...............................................................................................193
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