Administrator Guide

Congure both ends of the VLT interconnect trunk with identical PVST+ congurations. When you enable VLT, the show spanning-
tree pvst brief command output displays VLT information.
Dell#show spanning-tree pvst vlan 1000 brief
VLAN 1000
Executing IEEE compatible Spanning Tree Protocol
Root ID Priority 0, Address 90b1.1cf4.9b79
Root Bridge hello time 2, max age 20, forward delay 15
Bridge ID Priority 0, Address 90b1.1cf4.9b79
We are the root of Vlan 1000
Configured hello time 2, max age 20, forward delay 15
Interface Designated
Name PortID Prio Cost Sts Cost Bridge ID PortID
---------- -------- ---- ------ ----------- ------- -------------------- --------
Po 1 128.2 128 188 FWD(vltI) 0 0 90b1.1cf4.9b79 128.2
Po 2 128.3 128 2000 FWD(vlt) 0 0 90b1.1cf4.9b79 128.3
Te 1/10 128.230 128 2000 FWD 0 0 90b1.1cf4.9b79 128.230
Te 1/13 128.233 128 2000 FWD 0 0 90b1.1cf4.9b79 128.233
Interface
Name Role PortID Prio Cost Sts Cost Link-type Edge
---------- ------ -------- ---- ------- ----------- ------- --------- ----
Po 1 Desg 128.2 128 188 FWD 0
(vltI)P2P No
Po 2 Desg 128.3 128 2000 FWD 0 (vlt) P2P No
Te 1/10 Desg 128.230 128 2000 FWD 0 P2P Yes
Te 1/13 Desg 128.233 128 2000 FWD 0 P2P No
Dell#
Peer Routing Conguration Example
This section provides a detailed explanation of how to congure peer routing in a VLT domain.
In the following example, devices are congured as follows:
• Access switch A1 is connected to two VLT peers (Dell-1 and Dell-2).
• The two VLT peers are connected to an upstream switch R1.
• OSPF is congured in Dell-1, Dell-2, and R1 switches.
• Dell-1 is congured as the root bridge.
• Dell-1 is congured as the VLT primary.
• As the Router ID of Dell-1 is the highest in the topology (highest loopback address of 172.17.1.1), Dell-1 is the OSPF Designated Router.
• As the Router ID of Dell-2 is the second highest in the topology (172.16.1.1), Dell-2 is the OSPF Backup Designated Router.
1004
Virtual Link Trunking (VLT)