Users Guide

Chapter 59: Virtual Link Trunking (VLT)....................................................................................945
Overview...........................................................................................................................................................................945
VLT Terminology........................................................................................................................................................947
Layer-2 Traffic in VLT Domains.............................................................................................................................948
Interspersed VLANs..................................................................................................................................................949
VLT on Core Switches............................................................................................................................................. 949
Enhanced VLT............................................................................................................................................................950
Configure Virtual Link Trunking....................................................................................................................................951
Important Points to Remember..............................................................................................................................951
Configuration Notes................................................................................................................................................. 953
Primary and Secondary VLT Peers.......................................................................................................................955
RSTP and VLT........................................................................................................................................................... 956
VLT Bandwidth Monitoring.....................................................................................................................................956
VLT and Stacking......................................................................................................................................................956
VLT and IGMP Snooping......................................................................................................................................... 957
VLT IPv6......................................................................................................................................................................957
VLT Port Delayed Restoration............................................................................................................................... 957
Additional ARP Refresh on VLTi............................................................................................................................957
PIM-Sparse Mode Support on VLT...................................................................................................................... 958
VLT Routing .............................................................................................................................................................. 960
Non-VLT ARP Sync.................................................................................................................................................. 963
RSTP Configuration........................................................................................................................................................963
Preventing Forwarding Loops in a VLT Domain................................................................................................ 963
Sample RSTP configuration....................................................................................................................................964
Configuring VLT........................................................................................................................................................ 964
PVST+ Configuration..................................................................................................................................................... 973
Peer Routing Configuration Example......................................................................................................................... 974
Dell-1 Switch Configuration.................................................................................................................................... 975
Dell-2 Switch Configuration....................................................................................................................................978
R1 Configuration.........................................................................................................................................................981
Access Switch A1 Configurations and Verification........................................................................................... 982
eVLT Configuration Example........................................................................................................................................983
PIM-Sparse Mode Configuration Example............................................................................................................... 985
Verifying a VLT Configuration..................................................................................................................................... 986
Additional VLT Sample Configurations...................................................................................................................... 989
Troubleshooting VLT......................................................................................................................................................990
Reconfiguring Stacked Switches as VLT.................................................................................................................. 992
Specifying VLT Nodes in a PVLAN.............................................................................................................................992
Configuring a VLT VLAN or LAG in a PVLAN.......................................................................................................... 995
Creating a VLT LAG or a VLT VLAN.................................................................................................................... 995
Associating the VLT LAG or VLT VLAN in a PVLAN........................................................................................996
Proxy ARP Capability on VLT Peer Nodes................................................................................................................997
VLT Nodes as Rendezvous Points for Multicast Resiliency................................................................................. 998
Configuring VLAN-Stack over VLT............................................................................................................................ 998
IPv6 Peer Routing in VLT Domains Overview.........................................................................................................1001
Configure BFD in VLT Domain................................................................................................................................... 1006
Sample BFD configuration in VLT domain.........................................................................................................1006
VXLAN on VLT...............................................................................................................................................................1009
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