Administrator Guide
61 Virtual Link Trunking (VLT)....................................................................................................................... 976
Overview.........................................................................................................................................................................976
VLT Terminology.......................................................................................................................................................979
Layer-2 Trac in VLT Domains.............................................................................................................................. 980
Interspersed VLANs................................................................................................................................................. 981
VLT on Core Switches............................................................................................................................................. 981
Enhanced VLT.......................................................................................................................................................... 982
Congure Virtual Link Trunking.................................................................................................................................... 983
Important Points to Remember............................................................................................................................. 983
Conguration Notes................................................................................................................................................ 984
Primary and Secondary VLT Peers........................................................................................................................ 987
RSTP and VLT.......................................................................................................................................................... 987
VLT Bandwidth Monitoring.....................................................................................................................................988
VLT and Stacking.....................................................................................................................................................988
VLT and IGMP Snooping........................................................................................................................................ 988
VLT IPv6................................................................................................................................................................... 988
VLT Port Delayed Restoration................................................................................................................................989
PIM-Sparse Mode Support on VLT.......................................................................................................................989
VLT Routing ............................................................................................................................................................. 991
Non-VLT ARP Sync................................................................................................................................................. 994
RSTP Conguration...................................................................................................................................................... 995
Preventing Forwarding Loops in a VLT Domain................................................................................................... 995
Sample RSTP Conguration...................................................................................................................................995
Conguring VLT....................................................................................................................................................... 996
PVST+ Conguration...................................................................................................................................................1006
Sample PVST+ Conguration...............................................................................................................................1006
Peer Routing Conguration Example.........................................................................................................................1007
Dell-1 Switch Conguration...................................................................................................................................1008
Dell-2 Switch Conguration...................................................................................................................................1012
R1 Conguration......................................................................................................................................................1015
Access Switch A1 Congurations and Verication..............................................................................................1016
eVLT Conguration Example....................................................................................................................................... 1017
eVLT Conguration Step Examples...................................................................................................................... 1017
PIM-Sparse Mode Conguration Example................................................................................................................ 1019
Verifying a VLT Conguration.....................................................................................................................................1020
Additional VLT Sample Congurations.......................................................................................................................1023
Troubleshooting VLT.................................................................................................................................................... 1025
Reconguring Stacked Switches as VLT...................................................................................................................1026
Specifying VLT Nodes in a PVLAN............................................................................................................................ 1026
Association of VLTi as a Member of a PVLAN................................................................................................... 1027
MAC Synchronization for VLT Nodes in a PVLAN.............................................................................................1027
PVLAN Operations When One VLT Peer is Down............................................................................................. 1028
PVLAN Operations When a VLT Peer is Restarted........................................................................................... 1028
Interoperation of VLT Nodes in a PVLAN with ARP Requests.........................................................................1028
Scenarios for VLAN Membership and MAC Synchronization With VLT Nodes in PVLAN...........................1028
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