Deployment Guide

Table Of Contents
Configuring a Standard IP ACL Filter....................................................................................................................122
Configure an Extended IP ACL.....................................................................................................................................123
Configuring Filters with a Sequence Number..................................................................................................... 123
Configuring Filters Without a Sequence Number.............................................................................................. 125
Configure Layer 2 and Layer 3 ACLs.......................................................................................................................... 126
Assign an IP ACL to an Interface.................................................................................................................................126
Applying an IP ACL.......................................................................................................................................................... 126
Counting ACL Hits..................................................................................................................................................... 127
Configure Ingress ACLs..................................................................................................................................................127
Configure Egress ACLs.................................................................................................................................................. 128
Applying Egress Layer 3 ACLs (Control-Plane)..................................................................................................129
IP Prefix Lists....................................................................................................................................................................129
Configuration Task List for Prefix Lists................................................................................................................130
ACL Remarks.................................................................................................................................................................... 133
Configuring a Remark............................................................................................................................................... 133
Deleting a Remark......................................................................................................................................................133
ACL Resequencing.......................................................................................................................................................... 134
Resequencing an ACL or Prefix List......................................................................................................................134
Route Maps.......................................................................................................................................................................135
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........................................................................................................................... 145
Configure BFD for IPv6 Static Routes................................................................................................................. 148
Configure BFD for OSPF......................................................................................................................................... 150
Configure BFD for OSPFv3.....................................................................................................................................155
Configure BFD for IS-IS........................................................................................................................................... 157
Configure BFD for BGP............................................................................................................................................159
Configure BFD for VRRP......................................................................................................................................... 166
Configuring Protocol Liveness................................................................................................................................168
Chapter 9: Border Gateway Protocol (BGP)............................................................................... 169
BGP IP version 4 (BGPv4) Overview......................................................................................................................... 169
BGP Autonomous Systems..................................................................................................................................... 169
AS4 Number Representation................................................................................................................................... 171
Four-Byte AS Numbers.............................................................................................................................................173
BGP router ID..............................................................................................................................................................173
Sessions and Peers....................................................................................................................................................173
Establish a Session.....................................................................................................................................................173
BGP Attributes for selecting Best Path............................................................................................................... 174
Multiprotocol BGP..................................................................................................................................................... 179
BGP global and address family configuration..................................................................................................... 180
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