Conguring a Standard IP ACL Filter............................................................................................................................113
Congure an Extended IP ACL......................................................................................................................................114
Conguring Filters with a Sequence Number..............................................................................................................114
Conguring Filters Without a Sequence Number....................................................................................................... 114
Established Flag...............................................................................................................................................................115
Congure Layer 2 and Layer 3 ACLs............................................................................................................................ 115
Assign an IP ACL to an Interface...................................................................................................................................116
Applying an IP ACL..........................................................................................................................................................116
Counting ACL Hits...........................................................................................................................................................117
Congure Ingress ACLs.................................................................................................................................................. 117
Congure Egress ACLs...................................................................................................................................................117
Applying Egress Layer 3 ACLs (Control-Plane)........................................................................................................... 118
IP Prex Lists...................................................................................................................................................................118
Implementation Information.....................................................................................................................................119
Conguration Task List for Prex Lists.........................................................................................................................119
Creating a Prex List...................................................................................................................................................... 119
Creating a Prex List Without a Sequence Number..................................................................................................120
Viewing Prex Lists.........................................................................................................................................................121
Applying a Prex List for Route Redistribution............................................................................................................121
Applying a Filter to a Prex List (OSPF)......................................................................................................................122
ACL Resequencing......................................................................................................................................................... 122
Resequencing an ACL or Prex List.............................................................................................................................123
Route Maps..................................................................................................................................................................... 124
Implementation Information.....................................................................................................................................124
Important Points to Remember.................................................................................................................................... 125
Conguration Task List for Route Maps...................................................................................................................... 125
Creating a Route Map....................................................................................................................................................125
Congure Route Map Filters......................................................................................................................................... 126
Conguring Match Routes............................................................................................................................................ 127
Conguring Set Conditions........................................................................................................................................... 128
Congure a Route Map for Route Redistribution.......................................................................................................128
Congure a Route Map for Route Tagging................................................................................................................. 129
Continue Clause..............................................................................................................................................................129
Logging of ACL Processes............................................................................................................................................ 130
Guidelines for Conguring ACL Logging......................................................................................................................130
Conguring ACL Logging............................................................................................................................................... 131
Flow-Based Monitoring Support for ACLs...................................................................................................................131
Behavior of Flow-Based Monitoring.......................................................................................................................132
Enabling Flow-Based Monitoring..................................................................................................................................133
8 Bidirectional Forwarding Detection (BFD).................................................................................................. 135
How BFD Works............................................................................................................................................................. 135
BFD Packet Format..................................................................................................................................................136
BFD Sessions.............................................................................................................................................................137
BFD Three-Way Handshake.................................................................................................................................... 138
Session State Changes............................................................................................................................................140
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