Concept Guide

Displaying Uplink Failure Detection.............................................................................................................................. 973
Sample Conguration: Uplink Failure Detection.........................................................................................................975
58 Upgrade Procedures................................................................................................................................ 977
Get Help with Upgrades................................................................................................................................................977
59 Virtual LANs (VLANs).............................................................................................................................. 978
Default VLAN..................................................................................................................................................................979
Port-Based VLANs........................................................................................................................................................ 979
VLANs and Port Tagging.............................................................................................................................................. 980
Conguration Task List..................................................................................................................................................980
Creating a Port-Based VLAN.................................................................................................................................980
Assigning Interfaces to a VLAN..............................................................................................................................981
Moving Untagged Interfaces..................................................................................................................................982
Assigning an IP Address to a VLAN.......................................................................................................................983
Conguring Native VLANs........................................................................................................................................... 983
Enabling Null VLAN as the Default VLAN...................................................................................................................984
60 Virtual Link Trunking (VLT)...................................................................................................................... 985
Overview........................................................................................................................................................................ 985
VLT Terminology...................................................................................................................................................... 988
Layer-2 Trac in VLT Domains.............................................................................................................................. 989
Interspersed VLANs................................................................................................................................................ 990
VLT on Core Switches............................................................................................................................................ 990
Enhanced VLT...........................................................................................................................................................991
Congure Virtual Link Trunking.................................................................................................................................... 992
Important Points to Remember............................................................................................................................. 992
Conguration Notes................................................................................................................................................ 993
Primary and Secondary VLT Peers........................................................................................................................996
RSTP and VLT.......................................................................................................................................................... 997
VLT Bandwidth Monitoring.....................................................................................................................................997
VLT and Stacking..................................................................................................................................................... 997
VLT and IGMP Snooping.........................................................................................................................................997
VLT IPv6................................................................................................................................................................... 998
VLT Port Delayed Restoration................................................................................................................................998
PIM-Sparse Mode Support on VLT.......................................................................................................................998
VLT Routing ...........................................................................................................................................................1000
Non-VLT ARP Sync................................................................................................................................................1003
RSTP Conguration.....................................................................................................................................................1004
Preventing Forwarding Loops in a VLT Domain..................................................................................................1004
Sample RSTP conguration..................................................................................................................................1004
Conguring VLT..................................................................................................................................................... 1005
PVST+ Conguration....................................................................................................................................................1015
Sample PVST+ Conguration................................................................................................................................1016
Peer Routing Conguration Example......................................................................................................................... 1016
Dell-1 Switch Conguration....................................................................................................................................1017
Contents
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