Administrator Guide

Applying Egress ACLs...................................................................................................................................................116
Applying Layer 3 Egress ACLs on Control-Plane Traffic......................................................................................... 117
Counting ACL Hits........................................................................................................................................................ 117
IP Prefix Lists.......................................................................................................................................................................117
Configuration Task List for Prefix Lists......................................................................................................................118
ACL Remarks.......................................................................................................................................................................121
Configuring a Remark...................................................................................................................................................121
Deleting a Remark.........................................................................................................................................................121
ACL Resequencing.............................................................................................................................................................122
Resequencing an ACL or Prefix List.......................................................................................................................... 122
Route Maps........................................................................................................................................................................ 123
Important Points to Remember........................................................................................................................................124
Configuration Task List for Route Maps................................................................................................................... 124
Configuring Match Routes..........................................................................................................................................126
Configuring Set Conditions......................................................................................................................................... 127
Configure a Route Map for Route Redistribution.................................................................................................... 128
Configure a Route Map for Route Tagging.............................................................................................................. 128
Continue Clause........................................................................................................................................................... 128
Configuring a UDF ACL.....................................................................................................................................................129
Hot-Lock Behavior.............................................................................................................................................................130
7 Bidirectional Forwarding Detection (BFD)....................................................................................131
How BFD Works................................................................................................................................................................. 131
BFD Packet Format..................................................................................................................................................... 132
BFD Sessions................................................................................................................................................................ 133
BFD Three-Way Handshake....................................................................................................................................... 134
Session State Changes................................................................................................................................................135
Important Points to Remember....................................................................................................................................... 135
Configure BFD....................................................................................................................................................................135
Configure BFD for Physical Ports.............................................................................................................................. 136
Configure BFD for Static Routes............................................................................................................................... 137
Configure BFD for IPv6 Static Routes......................................................................................................................140
Configure BFD for OSPF............................................................................................................................................. 141
Configure BFD for OSPFv3........................................................................................................................................ 145
Configure BFD for IS-IS...............................................................................................................................................147
Configure BFD for BGP...............................................................................................................................................149
Configure BFD for VRRP............................................................................................................................................ 154
Configuring Protocol Liveness....................................................................................................................................157
8 Border Gateway Protocol IPv4 (BGPv4)......................................................................................158
Autonomous Systems (AS).............................................................................................................................................. 158
Sessions and Peers............................................................................................................................................................160
Establish a Session.......................................................................................................................................................160
Route Reflectors.................................................................................................................................................................161
BGP Attributes................................................................................................................................................................... 162
Best Path Selection Criteria........................................................................................................................................162
Weight........................................................................................................................................................................... 164
Local Preference.......................................................................................................................................................... 164
Multi-Exit Discriminators (MEDs).............................................................................................................................. 165
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