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Table Of Contents
Chapter 60: Virtual LANs (VLANs).............................................................................................898
Default VLAN................................................................................................................................................................... 898
Port-Based VLANs......................................................................................................................................................... 899
VLANs and Port Tagging.............................................................................................................................................. 899
Configuration Task List................................................................................................................................................. 900
Creating a Port-Based VLAN.................................................................................................................................900
Assigning Interfaces to a VLAN............................................................................................................................. 901
Moving Untagged Interfaces..................................................................................................................................902
Assigning an IP Address to a VLAN......................................................................................................................903
Configuring Native VLANs............................................................................................................................................903
Enabling Null VLAN as the Default VLAN................................................................................................................. 904
Chapter 61: Virtual Link Trunking (VLT).................................................................................... 905
Overview...........................................................................................................................................................................905
VLT Terminology....................................................................................................................................................... 907
Layer-2 Traffic in VLT Domains.............................................................................................................................908
Interspersed VLANs................................................................................................................................................. 909
VLT on Core Switches.............................................................................................................................................909
Enhanced VLT............................................................................................................................................................ 910
Configure Virtual Link Trunking.................................................................................................................................... 911
Important Points to Remember...............................................................................................................................911
Configuration Notes..................................................................................................................................................912
Primary and Secondary VLT Peers........................................................................................................................915
RSTP and VLT............................................................................................................................................................ 915
VLT Bandwidth Monitoring..................................................................................................................................... 916
VLT and Stacking.......................................................................................................................................................916
VLT and IGMP Snooping..........................................................................................................................................916
VLT IPv6...................................................................................................................................................................... 916
VLT Port Delayed Restoration................................................................................................................................916
PIM-Sparse Mode Support on VLT....................................................................................................................... 917
VLT Routing ............................................................................................................................................................... 918
Non-VLT ARP Sync...................................................................................................................................................921
RSTP Configuration........................................................................................................................................................ 921
Preventing Forwarding Loops in a VLT Domain................................................................................................ 922
Sample RSTP configuration....................................................................................................................................922
Configuring VLT........................................................................................................................................................ 923
PVST+ Configuration......................................................................................................................................................931
Peer Routing Configuration Example......................................................................................................................... 932
Dell-1 Switch Configuration.................................................................................................................................... 933
Dell-2 Switch Configuration....................................................................................................................................937
R1 Configuration........................................................................................................................................................940
Access Switch A1 Configurations and Verification............................................................................................ 941
eVLT Configuration Example........................................................................................................................................ 941
PIM-Sparse Mode Configuration Example................................................................................................................944
Verifying a VLT Configuration......................................................................................................................................944
Additional VLT Sample Configurations.......................................................................................................................947
Troubleshooting VLT......................................................................................................................................................949
Reconfiguring Stacked Switches as VLT..................................................................................................................950
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