Users Guide
55 Upgrade Procedures................................................................................................................................934
Get Help with Upgrades............................................................................................................................................... 934
56 Virtual LANs (VLANs)..............................................................................................................................935
Default VLAN................................................................................................................................................................. 936
Port-Based VLANs........................................................................................................................................................ 936
VLANs and Port Tagging...............................................................................................................................................937
Conguration Task List..................................................................................................................................................937
Creating a Port-Based VLAN................................................................................................................................. 937
Assigning Interfaces to a VLAN............................................................................................................................. 938
Moving Untagged Interfaces..................................................................................................................................939
Assigning an IP Address to a VLAN.......................................................................................................................940
Conguring Native VLANs........................................................................................................................................... 940
Enabling Null VLAN as the Default VLAN................................................................................................................... 941
57 Virtual Link Trunking (VLT).......................................................................................................................942
Overview.........................................................................................................................................................................942
VLT Terminology...................................................................................................................................................... 945
Layer-2 Trac in VLT Domains...............................................................................................................................946
Interspersed VLANs.................................................................................................................................................947
VLT on Core Switches.............................................................................................................................................947
Enhanced VLT.......................................................................................................................................................... 948
Congure Virtual Link Trunking.................................................................................................................................... 949
Important Points to Remember............................................................................................................................. 949
Conguration Notes................................................................................................................................................950
Primary and Secondary VLT Peers........................................................................................................................953
RSTP and VLT..........................................................................................................................................................953
VLT Bandwidth Monitoring.....................................................................................................................................954
VLT and Stacking.....................................................................................................................................................954
VLT and IGMP Snooping........................................................................................................................................ 954
VLT IPv6................................................................................................................................................................... 954
VLT Port Delayed Restoration................................................................................................................................955
PIM-Sparse Mode Support on VLT.......................................................................................................................955
VLT Routing .............................................................................................................................................................957
Non-VLT ARP Sync................................................................................................................................................. 960
RSTP Conguration....................................................................................................................................................... 961
Preventing Forwarding Loops in a VLT Domain....................................................................................................961
Sample RSTP Conguration................................................................................................................................... 961
Conguring VLT....................................................................................................................................................... 962
PVST+ Conguration.....................................................................................................................................................972
Sample PVST+ Conguration.................................................................................................................................972
Peer Routing Conguration Example.......................................................................................................................... 973
Dell-1 Switch Conguration.....................................................................................................................................974
Dell-2 Switch Conguration....................................................................................................................................978
R1 Conguration....................................................................................................................................................... 981
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