Concept Guide

VLANs and Port Tagging.............................................................................................................................................1044
Conguration Task List................................................................................................................................................ 1044
Creating a Port-Based VLAN................................................................................................................................1044
Assigning Interfaces to a VLAN............................................................................................................................1045
Moving Untagged Interfaces................................................................................................................................1046
Assigning an IP Address to a VLAN..................................................................................................................... 1047
Conguring Native VLANs..........................................................................................................................................1047
Enabling Null VLAN as the Default VLAN................................................................................................................. 1048
62 Virtual Link Trunking (VLT).....................................................................................................................1049
Overview.......................................................................................................................................................................1049
VLT Terminology.....................................................................................................................................................1052
Layer-2 Trac in VLT Domains.............................................................................................................................1053
Interspersed VLANs...............................................................................................................................................1054
VLT on Core Switches...........................................................................................................................................1054
Enhanced VLT........................................................................................................................................................ 1055
Congure Virtual Link Trunking.................................................................................................................................. 1056
Important Points to Remember............................................................................................................................1056
Conguration Notes...............................................................................................................................................1057
Primary and Secondary VLT Peers...................................................................................................................... 1060
RSTP and VLT.........................................................................................................................................................1061
VLT Bandwidth Monitoring....................................................................................................................................1061
VLT and Stacking....................................................................................................................................................1061
VLT and IGMP Snooping........................................................................................................................................1061
VLT IPv6..................................................................................................................................................................1062
VLT Port Delayed Restoration.............................................................................................................................. 1062
PIM-Sparse Mode Support on VLT..................................................................................................................... 1062
VLT Routing ........................................................................................................................................................... 1064
Non-VLT ARP Sync................................................................................................................................................1067
RSTP Conguration.....................................................................................................................................................1068
Preventing Forwarding Loops in a VLT Domain..................................................................................................1068
Sample RSTP conguration..................................................................................................................................1068
Conguring VLT......................................................................................................................................................1069
PVST+ Conguration................................................................................................................................................... 1079
Sample PVST+ Conguration............................................................................................................................... 1080
Peer Routing Conguration Example.........................................................................................................................1080
Dell-1 Switch Conguration....................................................................................................................................1081
Dell-2 Switch Conguration..................................................................................................................................1085
R1 Conguration.....................................................................................................................................................1088
Access Switch A1 Congurations and Verication.............................................................................................1089
eVLT Conguration Example...................................................................................................................................... 1090
eVLT Conguration Step Examples..................................................................................................................... 1090
PIM-Sparse Mode Conguration Example............................................................................................................... 1092
Verifying a VLT Conguration.....................................................................................................................................1093
Additional VLT Sample Congurations...................................................................................................................... 1096
Troubleshooting VLT.................................................................................................................................................... 1098
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