Users Guide

Assigning an IP Address to a VLAN.......................................................................................................................928
Configuring Native VLANs........................................................................................................................................... 928
Enabling Null VLAN as the Default VLAN...................................................................................................................929
56 Virtual Link Trunking (VLT)..................................................................................................................... 930
Overview........................................................................................................................................................................ 930
VLT Terminology......................................................................................................................................................933
Layer-2 Traffic in VLT Domains.............................................................................................................................934
Interspersed VLANs................................................................................................................................................ 935
VLT on Core Switches............................................................................................................................................935
Enhanced VLT..........................................................................................................................................................936
Configure Virtual Link Trunking....................................................................................................................................937
Important Points to Remember............................................................................................................................. 937
Configuration Notes................................................................................................................................................938
Primary and Secondary VLT Peers........................................................................................................................ 941
RSTP and VLT.......................................................................................................................................................... 941
VLT Bandwidth Monitoring.................................................................................................................................... 942
VLT and Stacking.................................................................................................................................................... 942
VLT and IGMP Snooping........................................................................................................................................ 942
VLT IPv6...................................................................................................................................................................942
VLT Port Delayed Restoration............................................................................................................................... 943
PIM-Sparse Mode Support on VLT...................................................................................................................... 943
VLT Routing ............................................................................................................................................................ 945
Non-VLT ARP Sync................................................................................................................................................ 948
RSTP Configuration...................................................................................................................................................... 949
Preventing Forwarding Loops in a VLT Domain.................................................................................................. 949
Sample RSTP Configuration.................................................................................................................................. 949
Configuring VLT.......................................................................................................................................................950
PVST+ Configuration....................................................................................................................................................960
Sample PVST+ Configuration................................................................................................................................960
Peer Routing Configuration Example...........................................................................................................................961
Dell-1 Switch Configuration....................................................................................................................................962
Dell-2 Switch Configuration...................................................................................................................................966
R1 Configuration...................................................................................................................................................... 969
Access Switch A1 Configurations and Verification..............................................................................................970
eVLT Configuration Example........................................................................................................................................ 971
eVLT Configuration Step Examples....................................................................................................................... 971
PIM-Sparse Mode Configuration Example.................................................................................................................973
Verifying a VLT Configuration......................................................................................................................................974
Additional VLT Sample Configurations........................................................................................................................977
Troubleshooting VLT.....................................................................................................................................................979
Reconfiguring Stacked Switches as VLT................................................................................................................... 980
Specifying VLT Nodes in a PVLAN............................................................................................................................. 980
Association of VLTi as a Member of a PVLAN.....................................................................................................981
MAC Synchronization for VLT Nodes in a PVLAN.............................................................................................. 981
PVLAN Operations When One VLT Peer is Down..............................................................................................982
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