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Table Of Contents
Configure Ingress ACLs..................................................................................................................................................120
Configure Egress ACLs................................................................................................................................................... 121
Applying Egress Layer 3 ACLs (Control-Plane).................................................................................................. 121
IP Prefix Lists....................................................................................................................................................................122
Configuration Task List for Prefix Lists................................................................................................................122
ACL Remarks.................................................................................................................................................................... 125
Configuring a Remark............................................................................................................................................... 126
Deleting a Remark......................................................................................................................................................126
ACL Resequencing...........................................................................................................................................................127
Resequencing an ACL or Prefix List...................................................................................................................... 127
Route Maps.......................................................................................................................................................................128
Logging of ACL Processes............................................................................................................................................ 129
Guidelines for Configuring ACL Logging.............................................................................................................. 129
Configuring ACL Logging......................................................................................................................................... 130
Flow-Based Monitoring.................................................................................................................................................. 130
Enabling Flow-Based Monitoring............................................................................................................................132
Configuring UDF ACL..................................................................................................................................................... 133
Configuring IP Mirror Access Group........................................................................................................................... 135
Sample Configuration................................................................................................................................................136
Example of viewing IP mirroraccessgroup applied to an Interface.......................................................... 136
Chapter 8: Bidirectional Forwarding Detection (BFD).................................................................137
How BFD Works............................................................................................................................................................... 137
BFD Packet Format...................................................................................................................................................138
BFD Sessions.............................................................................................................................................................. 139
BFD Three-Way Handshake.................................................................................................................................... 140
Session State Changes..............................................................................................................................................141
Important Points to Remember.....................................................................................................................................141
Configure BFD...................................................................................................................................................................141
Configure BFD for Physical Ports..........................................................................................................................142
Configure BFD for Static Routes........................................................................................................................... 143
Configure BFD for IPv6 Static Routes..................................................................................................................147
Configure BFD for OSPF......................................................................................................................................... 149
Configure BFD for OSPFv3.....................................................................................................................................154
Configure BFD for IS-IS........................................................................................................................................... 156
Configure BFD for BGP............................................................................................................................................158
Configure BFD for VRRP......................................................................................................................................... 165
Configuring Protocol Liveness................................................................................................................................ 167
Chapter 9: Border Gateway Protocol (BGP)............................................................................... 168
BGP IP version 4 (BGPv4) Overview......................................................................................................................... 168
BGP Autonomous Systems......................................................................................................................................168
AS4 Number Representation...................................................................................................................................170
Four-Byte AS Numbers.............................................................................................................................................172
BGP router ID..............................................................................................................................................................172
Sessions and Peers....................................................................................................................................................172
Establish a Session.....................................................................................................................................................172
BGP Attributes for selecting Best Path............................................................................................................... 173
Multiprotocol BGP..................................................................................................................................................... 178
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