Users Guide

65 Virtual Link Trunking (VLT)........................................................................................ 891
Overview........................................................................................................................................................................ 891
VLT on Core Switches..............................................................................................................................................892
Multiple VLT............................................................................................................................................................. 893
VLT Terminology.............................................................................................................................................................894
Congure Virtual Link Trunking.......................................................................................................................................894
Important Points to Remember................................................................................................................................894
Conguration Notes.................................................................................................................................................895
RSTP and VLT..........................................................................................................................................................898
VLT Bandwidth Monitoring.......................................................................................................................................898
VLT and Stacking..................................................................................................................................................... 898
VLT and IGMP Snooping..........................................................................................................................................898
VLT Port Delayed Restoration.................................................................................................................................. 899
PIM-Sparse Mode Support on VLT.......................................................................................................................... 899
RSTP Conguration........................................................................................................................................................901
Preventing Forwarding Loops in a VLT Domain......................................................................................................... 901
Sample RSTP Conguration..................................................................................................................................... 901
Conguring VLT....................................................................................................................................................... 902
Conguring a VLT Interconnect................................................................................................................................902
Enabling VLT and Creating a VLT Domain.................................................................................................................903
Conguring a VLT Backup Link................................................................................................................................ 903
Conguring a VLT Port Delay Period........................................................................................................................ 904
Reconguring the Default VLT Settings (Optional) ................................................................................................. 904
Connecting a VLT Domain to an Attached Access Device (Switch or Server)..........................................................905
Conguring a VLT VLAN Peer-Down (Optional)...................................................................................................... 906
Conguring Enhanced VLT (eVLT) (Optional)..........................................................................................................906
PVST+ Conguration..................................................................................................................................................... 908
Sample PVST+ Conguration...................................................................................................................................908
VLT Sample Conguration..............................................................................................................................................909
eVLT Conguration Example...........................................................................................................................................912
eVLT Conguration Step Examples...........................................................................................................................913
PIM-Sparse Mode Conguration Example...................................................................................................................... 915
Verifying a VLT Conguration......................................................................................................................................... 915
Additional VLT Sample Congurations.............................................................................................................................919
Conguring Virtual Link Trunking (VLT Peer 1)Conguring Virtual Link Trunking (VLT Peer 2)Verifying a Port-
Channel Connection to a VLT Domain (From an Attached Access Switch)...............................................................919
Troubleshooting VLT....................................................................................................................................................... 921
Reconguring Stacked Switches as VLT........................................................................................................................ 922
Specifying VLT Nodes in a PVLAN................................................................................................................................. 922
Association of VLTi as a Member of a PVLAN..........................................................................................................923
MAC Synchronization for VLT Nodes in a PVLAN....................................................................................................923
PVLAN Operations When One VLT Peer is Down.................................................................................................... 924
PVLAN Operations When a VLT Peer is Restarted...................................................................................................924
Interoperation of VLT Nodes in a PVLAN with ARP Requests.................................................................................. 924
Scenarios for VLAN Membership and MAC Synchronization With VLT Nodes in PVLAN.........................................924
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