Users Guide

Congure a Route Map for Route Redistribution..................................................................................................116
Congure a Route Map for Route Tagging............................................................................................................ 117
Continue Clause.........................................................................................................................................................117
IP Fragment Handling..................................................................................................................................................... 117
IP Fragments ACL Examples................................................................................................................................... 118
Layer 4 ACL Rules Examples................................................................................................................................... 118
Congure a Standard IP ACL.........................................................................................................................................119
Conguring a Standard IP ACL Filter..................................................................................................................... 120
Congure an Extended IP ACL......................................................................................................................................121
Conguring Filters with a Sequence Number........................................................................................................121
Conguring Filters Without a Sequence Number.................................................................................................124
Congure Layer 2 and Layer 3 ACLs............................................................................................................................124
Assign an IP ACL to an Interface..................................................................................................................................125
Applying an IP ACL.........................................................................................................................................................125
Counting ACL Hits....................................................................................................................................................126
Congure Ingress ACLs................................................................................................................................................. 126
Congure Egress ACLs.................................................................................................................................................. 127
Applying Egress Layer 3 ACLs (Control-Plane).................................................................................................... 128
IP Prex Lists.................................................................................................................................................................. 128
Implementation Information.................................................................................................................................... 129
Conguration Task List for Prex Lists.................................................................................................................. 129
ACL Resequencing......................................................................................................................................................... 132
Resequencing an ACL or Prex List.......................................................................................................................133
Route Maps.....................................................................................................................................................................134
Implementation Information.................................................................................................................................... 134
Flow-Based Monitoring Support for ACLs.................................................................................................................. 134
Behavior of Flow-Based Monitoring.......................................................................................................................135
Enabling Flow-Based Monitoring............................................................................................................................136
Conguring IP Mirror Access Group............................................................................................................................ 136
Sample Conguration...............................................................................................................................................137
Example of viewing IP mirror–access–group applied to an Interface................................................................138
7 Bidirectional Forwarding Detection (BFD).................................................................................................. 139
How BFD Works............................................................................................................................................................. 139
BFD Packet Format..................................................................................................................................................140
BFD Sessions............................................................................................................................................................. 141
BFD Three-Way Handshake.................................................................................................................................... 142
Session State Changes............................................................................................................................................144
Important Points to Remember.................................................................................................................................... 144
Congure BFD................................................................................................................................................................ 144
Congure BFD for Physical Ports...........................................................................................................................145
Congure BFD for Static Routes............................................................................................................................148
Congure BFD for OSPF..........................................................................................................................................151
Congure BFD for OSPFv3.....................................................................................................................................156
Congure BFD for IS-IS...........................................................................................................................................158
Congure BFD for BGP...........................................................................................................................................160
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