Administrator Guide

Configure Ingress ACLs.................................................................................................................................................. 121
Configure Egress ACLs.................................................................................................................................................. 122
Applying Egress Layer 3 ACLs (Control-Plane)..................................................................................................122
IP Prefix Lists....................................................................................................................................................................123
Configuration Task List for Prefix Lists................................................................................................................123
ACL Remarks.................................................................................................................................................................... 126
Configuring a Remark................................................................................................................................................127
Deleting a Remark......................................................................................................................................................127
ACL Resequencing.......................................................................................................................................................... 128
Resequencing an ACL or Prefix List......................................................................................................................128
Route Maps.......................................................................................................................................................................129
Logging of ACL Processes............................................................................................................................................ 130
Guidelines for Configuring ACL Logging.............................................................................................................. 130
Configuring ACL Logging..........................................................................................................................................131
Flow-Based Monitoring................................................................................................................................................... 131
Enabling Flow-Based Monitoring............................................................................................................................133
Configuring UDF ACL..................................................................................................................................................... 134
Configuring IP Mirror Access Group........................................................................................................................... 136
Sample Configuration................................................................................................................................................137
Example of viewing IP mirror–access–group applied to an Interface...........................................................137
Chapter 8: Bidirectional Forwarding Detection (BFD)................................................................ 138
How BFD Works...............................................................................................................................................................138
BFD Packet Format...................................................................................................................................................139
BFD Sessions.............................................................................................................................................................. 140
BFD Three-Way Handshake.....................................................................................................................................141
Session State Changes.............................................................................................................................................142
Important Points to Remember....................................................................................................................................142
Configure BFD.................................................................................................................................................................. 142
Configure BFD for Physical Ports..........................................................................................................................143
Configure BFD for Static Routes........................................................................................................................... 144
Configure BFD for IPv6 Static Routes................................................................................................................. 148
Configure BFD for OSPF......................................................................................................................................... 150
Configure BFD for OSPFv3.....................................................................................................................................155
Configure BFD for IS-IS........................................................................................................................................... 158
Configure BFD for BGP............................................................................................................................................160
Configure BFD for VRRP......................................................................................................................................... 166
Configuring Protocol Liveness................................................................................................................................169
Chapter 9: Border Gateway Protocol (BGP)............................................................................... 170
BGP IP version 4 (BGPv4) Overview......................................................................................................................... 170
BGP Autonomous Systems......................................................................................................................................170
AS4 Number Representation...................................................................................................................................172
Four-Byte AS Numbers.............................................................................................................................................174
BGP router ID..............................................................................................................................................................174
Sessions and Peers....................................................................................................................................................174
Establish a Session.....................................................................................................................................................174
BGP Attributes for selecting Best Path............................................................................................................... 175
Multiprotocol BGP..................................................................................................................................................... 180
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