Concept Guide

Table Of Contents
Overview...........................................................................................................................................................................902
VLT Terminology....................................................................................................................................................... 904
Layer-2 Traffic in VLT Domains............................................................................................................................ 905
Interspersed VLANs................................................................................................................................................. 906
VLT on Core Switches.............................................................................................................................................906
Enhanced VLT............................................................................................................................................................907
Configure Virtual Link Trunking...................................................................................................................................908
Important Points to Remember.............................................................................................................................908
Configuration Notes................................................................................................................................................. 909
Primary and Secondary VLT Peers........................................................................................................................912
RSTP and VLT............................................................................................................................................................ 912
VLT Bandwidth Monitoring......................................................................................................................................913
VLT and Stacking.......................................................................................................................................................913
VLT and IGMP Snooping..........................................................................................................................................913
VLT IPv6...................................................................................................................................................................... 913
VLT Port Delayed Restoration................................................................................................................................914
PIM-Sparse Mode Support on VLT....................................................................................................................... 914
VLT Routing ............................................................................................................................................................... 916
Non-VLT ARP Sync...................................................................................................................................................919
RSTP Configuration........................................................................................................................................................ 919
Preventing Forwarding Loops in a VLT Domain................................................................................................. 919
Sample RSTP configuration....................................................................................................................................920
Configuring VLT........................................................................................................................................................ 920
PVST+ Configuration.....................................................................................................................................................929
Peer Routing Configuration Example.........................................................................................................................930
Dell-1 Switch Configuration.................................................................................................................................... 930
Dell-2 Switch Configuration................................................................................................................................... 934
R1 Configuration........................................................................................................................................................ 937
Access Switch A1 Configurations and Verification........................................................................................... 938
eVLT Configuration Example........................................................................................................................................939
PIM-Sparse Mode Configuration Example................................................................................................................ 941
Verifying a VLT Configuration...................................................................................................................................... 941
Additional VLT Sample Configurations...................................................................................................................... 945
Troubleshooting VLT......................................................................................................................................................946
Reconfiguring Stacked Switches as VLT.................................................................................................................. 947
Specifying VLT Nodes in a PVLAN.............................................................................................................................948
Configuring a VLT VLAN or LAG in a PVLAN...........................................................................................................951
Creating a VLT LAG or a VLT VLAN..................................................................................................................... 951
Associating the VLT LAG or VLT VLAN in a PVLAN........................................................................................952
Proxy ARP Capability on VLT Peer Nodes................................................................................................................953
VLT Nodes as Rendezvous Points for Multicast Resiliency................................................................................. 954
Configuring VLAN-Stack over VLT............................................................................................................................ 954
IPv6 Peer Routing in VLT Domains Overview..........................................................................................................957
Configure BFD in VLT Domain......................................................................................................................................961
Sample BFD configuration in VLT domain........................................................................................................... 961
Chapter 59: VLT Proxy Gateway................................................................................................ 966
Proxy Gateway in VLT Domains..................................................................................................................................966
LLDP VLT Proxy Gateway in a Square VLT Topology..................................................................................... 969
Configuring a Static VLT Proxy Gateway................................................................................................................. 970
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