Conguring Filters with a Sequence Number..................................................................................................................106
Conguring Filters Without a Sequence Number............................................................................................................ 107
Established Flag.............................................................................................................................................................. 107
Congure Layer 2 and Layer 3 ACLs............................................................................................................................... 107
Assign an IP ACL to an Interface.....................................................................................................................................108
Applying an IP ACL......................................................................................................................................................... 108
Counting ACL Hits.......................................................................................................................................................... 109
Congure Ingress ACLs.................................................................................................................................................. 109
Congure Egress ACLs....................................................................................................................................................110
Applying Egress Layer 3 ACLs (Control-Plane)................................................................................................................ 110
IP Prex Lists................................................................................................................................................................... 111
Implementation Information........................................................................................................................................111
Conguration Task List for Prex Lists..............................................................................................................................111
Creating a Prex List....................................................................................................................................................... 112
Creating a Prex List Without a Sequence Number.........................................................................................................112
Viewing Prex Lists..........................................................................................................................................................113
Applying a Prex List for Route Redistribution.................................................................................................................114
Applying a Filter to a Prex List (OSPF)...........................................................................................................................114
ACL Resequencing.......................................................................................................................................................... 115
Resequencing an ACL or Prex List.................................................................................................................................115
Route Maps..................................................................................................................................................................... 117
Implementation Information....................................................................................................................................... 117
Important Points to Remember........................................................................................................................................117
Conguration Task List for Route Maps........................................................................................................................... 117
Creating a Route Map......................................................................................................................................................117
Congure Route Map Filters............................................................................................................................................119
Conguring Match Routes...............................................................................................................................................119
Conguring Set Conditions.............................................................................................................................................120
Congure a Route Map for Route Redistribution............................................................................................................. 121
Congure a Route Map for Route Tagging.......................................................................................................................121
Continue Clause..............................................................................................................................................................122
Logging of ACL Processes.............................................................................................................................................. 122
Guidelines for Conguring ACL Logging..........................................................................................................................123
Conguring ACL Logging................................................................................................................................................ 123
Flow-Based Monitoring Support for ACLs.......................................................................................................................124
Behavior of Flow-Based Monitoring.......................................................................................................................... 124
Enabling Flow-Based Monitoring.....................................................................................................................................126
8 Bidirectional Forwarding Detection (BFD).................................................................... 127
How BFD Works..............................................................................................................................................................127
BFD Packet Format.................................................................................................................................................. 128
BFD Sessions............................................................................................................................................................129
BFD Three-Way Handshake...................................................................................................................................... 130
Session State Changes............................................................................................................................................. 132
Important Points to Remember.......................................................................................................................................132
Congure BFD................................................................................................................................................................ 132
6