White Papers

Enabling Null VLAN as the Default VLAN...................................................................................................................935
56 Virtual Link Trunking (VLT)...................................................................................................................... 936
Overview.........................................................................................................................................................................936
VLT Terminology...................................................................................................................................................... 939
Layer-2 Trac in VLT Domains.............................................................................................................................. 940
Interspersed VLANs................................................................................................................................................. 941
VLT on Core Switches............................................................................................................................................. 941
Enhanced VLT.......................................................................................................................................................... 942
Congure Virtual Link Trunking.................................................................................................................................... 943
Important Points to Remember............................................................................................................................. 943
Conguration Notes................................................................................................................................................ 944
Primary and Secondary VLT Peers........................................................................................................................947
RSTP and VLT..........................................................................................................................................................947
VLT Bandwidth Monitoring.....................................................................................................................................948
VLT and Stacking.....................................................................................................................................................948
VLT and IGMP Snooping........................................................................................................................................ 948
VLT IPv6................................................................................................................................................................... 948
VLT Port Delayed Restoration................................................................................................................................949
PIM-Sparse Mode Support on VLT.......................................................................................................................949
VLT Routing ..............................................................................................................................................................951
Non-VLT ARP Sync................................................................................................................................................. 954
RSTP Conguration...................................................................................................................................................... 955
Preventing Forwarding Loops in a VLT Domain...................................................................................................955
Sample RSTP Conguration.................................................................................................................................. 955
Conguring VLT.......................................................................................................................................................956
PVST+ Conguration.................................................................................................................................................... 966
Sample PVST+ Conguration.................................................................................................................................966
Peer Routing Conguration Example.......................................................................................................................... 967
Dell-1 Switch Conguration.................................................................................................................................... 968
Dell-2 Switch Conguration....................................................................................................................................972
R1 Conguration.......................................................................................................................................................975
Access Switch A1 Congurations and Verication...............................................................................................976
eVLT Conguration Example........................................................................................................................................ 977
eVLT Conguration Step Examples....................................................................................................................... 977
PIM-Sparse Mode Conguration Example................................................................................................................. 979
Verifying a VLT Conguration...................................................................................................................................... 980
Additional VLT Sample Congurations........................................................................................................................ 983
Troubleshooting VLT......................................................................................................................................................985
Reconguring Stacked Switches as VLT....................................................................................................................986
Specifying VLT Nodes in a PVLAN..............................................................................................................................986
Association of VLTi as a Member of a PVLAN.....................................................................................................987
MAC Synchronization for VLT Nodes in a PVLAN.............................................................................................. 987
PVLAN Operations When One VLT Peer is Down...............................................................................................988
PVLAN Operations When a VLT Peer is Restarted.............................................................................................988
Interoperation of VLT Nodes in a PVLAN with ARP Requests.......................................................................... 988
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