Deployment Guide

Table Of Contents
Applying Egress ACLs................................................................................................................................................119
Applying Layer 3 Egress ACLs on Control-Plane Traffic.................................................................................. 119
Counting ACL Hits.....................................................................................................................................................120
IP Prefix Lists....................................................................................................................................................................120
Configuration Task List for Prefix Lists.................................................................................................................121
ACL Remarks.................................................................................................................................................................... 124
Configuring a Remark............................................................................................................................................... 124
Deleting a Remark......................................................................................................................................................124
ACL Resequencing.......................................................................................................................................................... 125
Resequencing an ACL or Prefix List......................................................................................................................125
Route Maps.......................................................................................................................................................................126
Important Points to Remember.................................................................................................................................... 127
Configuration Task List for Route Maps.............................................................................................................. 127
Configuring Match Routes...................................................................................................................................... 129
Configuring Set Conditions..................................................................................................................................... 130
Configure a Route Map for Route Redistribution............................................................................................... 131
Configure a Route Map for Route Tagging.......................................................................................................... 131
Continue Clause......................................................................................................................................................... 132
Configuring a UDF ACL.................................................................................................................................................. 132
Hot-Lock Behavior.......................................................................................................................................................... 134
Chapter 7: Bidirectional Forwarding Detection (BFD).................................................................135
How BFD Works...............................................................................................................................................................135
BFD Packet Format...................................................................................................................................................136
BFD Sessions...............................................................................................................................................................137
BFD Three-Way Handshake.................................................................................................................................... 138
Session State Changes.............................................................................................................................................139
Important Points to Remember....................................................................................................................................139
Configure BFD.................................................................................................................................................................. 139
Configure BFD for Physical Ports..........................................................................................................................140
Configure BFD for Static Routes............................................................................................................................141
Configure BFD for IPv6 Static Routes................................................................................................................. 144
Configure BFD for OSPF......................................................................................................................................... 145
Configure BFD for OSPFv3.....................................................................................................................................150
Configure BFD for IS-IS........................................................................................................................................... 152
Configure BFD for BGP............................................................................................................................................154
Configure BFD for VRRP......................................................................................................................................... 160
Configuring Protocol Liveness................................................................................................................................162
Chapter 8: Border Gateway Protocol IPv4 (BGPv4)....................................................................163
Autonomous Systems (AS)........................................................................................................................................... 163
Sessions and Peers......................................................................................................................................................... 165
Establish a Session.................................................................................................................................................... 165
Route Reflectors..............................................................................................................................................................166
BGP Attributes................................................................................................................................................................. 167
Best Path Selection Criteria.................................................................................................................................... 167
Weight.......................................................................................................................................................................... 169
Local Preference........................................................................................................................................................169
Multi-Exit Discriminators (MEDs).......................................................................................................................... 170
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Contents