Congure an Extended IP ACL......................................................................................................................................112
Conguring Filters with a Sequence Number..............................................................................................................112
Conguring Filters Without a Sequence Number....................................................................................................... 113
Established Flag...............................................................................................................................................................113
Congure Layer 2 and Layer 3 ACLs............................................................................................................................ 113
Assign an IP ACL to an Interface...................................................................................................................................114
Applying an IP ACL..........................................................................................................................................................114
Counting ACL Hits.......................................................................................................................................................... 115
Congure Ingress ACLs..................................................................................................................................................115
Congure Egress ACLs...................................................................................................................................................116
Applying Egress Layer 3 ACLs (Control-Plane)...........................................................................................................116
IP Prex Lists................................................................................................................................................................... 117
Implementation Information..................................................................................................................................... 117
Conguration Task List for Prex Lists......................................................................................................................... 117
Creating a Prex List.......................................................................................................................................................118
Creating a Prex List Without a Sequence Number...................................................................................................118
Viewing Prex Lists.........................................................................................................................................................119
Applying a Prex List for Route Redistribution...........................................................................................................120
Applying a Filter to a Prex List (OSPF)......................................................................................................................120
ACL Resequencing..........................................................................................................................................................121
Resequencing an ACL or Prex List..............................................................................................................................121
Route Maps..................................................................................................................................................................... 123
Implementation Information.................................................................................................................................... 123
Important Points to Remember.................................................................................................................................... 123
Conguration Task List for Route Maps...................................................................................................................... 123
Creating a Route Map....................................................................................................................................................123
Congure Route Map Filters.........................................................................................................................................125
Conguring Match Routes............................................................................................................................................ 125
Conguring Set Conditions........................................................................................................................................... 126
Congure a Route Map for Route Redistribution....................................................................................................... 127
Congure a Route Map for Route Tagging..................................................................................................................127
Continue Clause..............................................................................................................................................................128
Logging of ACL Processes............................................................................................................................................ 128
Guidelines for Conguring ACL Logging......................................................................................................................129
Conguring ACL Logging...............................................................................................................................................129
Flow-Based Monitoring Support for ACLs..................................................................................................................130
Behavior of Flow-Based Monitoring.......................................................................................................................130
Enabling Flow-Based Monitoring...................................................................................................................................131
8 Bidirectional Forwarding Detection (BFD).................................................................................................. 133
How BFD Works............................................................................................................................................................. 133
BFD Packet Format..................................................................................................................................................134
BFD Sessions............................................................................................................................................................ 135
BFD Three-Way Handshake.................................................................................................................................... 136
Session State Changes............................................................................................................................................138
Important Points to Remember.................................................................................................................................... 138
6
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