Concept Guide

Conguring Native VLANs...................................................................................................................................... 918
Enabling Null VLAN as the Default VLAN................................................................................................................... 919
65 Virtual Link Trunking (VLT)...................................................................................................................... 920
Overview.........................................................................................................................................................................920
Multi-domain VLT..................................................................................................................................................... 921
VLT Terminology.............................................................................................................................................................922
Congure Virtual Link Trunking.................................................................................................................................... 922
Important Points to Remember............................................................................................................................. 922
Conguration Notes................................................................................................................................................ 923
RSTP and VLT..........................................................................................................................................................926
VLT Bandwidth Monitoring.....................................................................................................................................926
VLT and IGMP Snooping.........................................................................................................................................927
VLT Port Delayed Restoration................................................................................................................................ 927
PIM-Sparse Mode Support on VLT....................................................................................................................... 927
VLT Multicast........................................................................................................................................................... 929
VLT Unicast Routing................................................................................................................................................930
Non-VLT ARP Sync.................................................................................................................................................. 931
RSTP Conguration....................................................................................................................................................... 931
Preventing Forwarding Loops in a VLT Domain.................................................................................................... 931
Sample RSTP Conguration...................................................................................................................................932
Conguring VLT....................................................................................................................................................... 932
Conguring a VLT Interconnect.............................................................................................................................932
Conguring a VLT Backup Link..............................................................................................................................933
Conguring a VLT Port Delay Period.....................................................................................................................934
Reconguring the Default VLT Settings (Optional) ............................................................................................934
Connecting a VLT Domain to an Attached Access Device (Switch or Server)............................................... 935
Conguring a VLT VLAN Peer-Down (Optional)................................................................................................. 936
Congure Multi-domain VLT (mVLT) (Optional)................................................................................................. 936
Verifying a VLT Conguration.................................................................................................................................938
Connecting a VLT Domain.......................................................................................................................................941
PVST+ Conguration.................................................................................................................................................... 945
Sample PVST+ Conguration.................................................................................................................................945
mVLT Conguration Example.......................................................................................................................................946
In Domain 1, congure the VLT domain and VLTi on Peer 1Congure mVLT on Peer 1Add links to the
mVLT port-channel on Peer 1Next, congure the VLT domain and VLTi on Peer 2Congure mVLT on
Peer 2Add links to the mVLT port-channel on Peer 2In Domain 2, congure the VLT domain and VLTi
on Peer 3Congure mVLT on Peer 3Add links to the mVLT port-channel on Peer 3Congure the VLT
domain and VLTi on Peer 4Congure mVLT on Peer 4Add links to the mVLT port-channel on Peer 4....... 947
PIM-Sparse Mode Conguration Example.................................................................................................................949
Additional VLT Sample Congurations........................................................................................................................950
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)...........................................950
Troubleshooting VLT......................................................................................................................................................952
Specifying VLT Nodes in a PVLAN..............................................................................................................................953
Association of VLTi as a Member of a PVLAN.....................................................................................................954
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