Users Guide
Configuring a Standard IP ACL Filter.............................................................................................................112
Configure an Extended IP ACL.............................................................................................................................113
Configuring Filters with a Sequence Number.............................................................................................113
Configuring Filters Without a Sequence Number......................................................................................114
Configure Layer 2 and Layer 3 ACLs...................................................................................................................115
Assign an IP ACL to an Interface..........................................................................................................................115
Applying an IP ACL..................................................................................................................................................115
Counting ACL Hits............................................................................................................................................ 116
Configure Ingress ACLs......................................................................................................................................... 116
Configure Egress ACLs...........................................................................................................................................117
Applying Egress Layer 3 ACLs (Control-Plane)...........................................................................................118
IP Prefix Lists............................................................................................................................................................ 118
Implementation Information.......................................................................................................................... 119
Configuration Task List for Prefix Lists......................................................................................................... 119
ACL Resequencing................................................................................................................................................. 122
Resequencing an ACL or Prefix List.............................................................................................................. 123
Route Maps.............................................................................................................................................................. 124
Implementation Information..........................................................................................................................124
Logging of ACL Processes....................................................................................................................................124
Guidelines for Configuring ACL Logging.....................................................................................................125
Configuring ACL Logging............................................................................................................................... 126
Flow-Based Monitoring Support for ACLs........................................................................................................ 126
Behavior of Flow-Based Monitoring.............................................................................................................127
Enabling Flow-Based Monitoring..................................................................................................................128
8 Bidirectional Forwarding Detection (BFD)..................................................................................................... 130
How BFD Works......................................................................................................................................................130
BFD Packet Format........................................................................................................................................... 131
BFD Sessions......................................................................................................................................................132
BFD Three-Way Handshake........................................................................................................................... 133
Session State Changes.....................................................................................................................................135
Important Points to Remember...........................................................................................................................135
Configure BFD.........................................................................................................................................................135
Configure BFD for Physical Ports..................................................................................................................136
Configure BFD for Static Routes................................................................................................................... 139
Configure BFD for OSPF..................................................................................................................................141
Configure BFD for OSPFv3............................................................................................................................. 144
Configure BFD for IS-IS...................................................................................................................................145
Configure BFD for BGP....................................................................................................................................147
Configure BFD for VRRP................................................................................................................................. 154
Configuring Protocol Liveness.......................................................................................................................156
Troubleshooting BFD.......................................................................................................................................156
9 Border Gateway Protocol IPv4 (BGPv4)......................................................................................................... 158
Autonomous Systems (AS)....................................................................................................................................158
Sessions and Peers.................................................................................................................................................160
Establish a Session............................................................................................................................................ 161
9.10(0.1)
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