Reference Guide
Virtual Link Trunking (VLT) | 1037
Figure 53-10. show spanning-tree rstp Command Output on VLT peer switches
Sample Configuration: Virtual Link Trunking
To configure virtual link trunking, you must configure a backup link and interconnect trunk, create a VLT
domain, configure a backup link and interconnect trunk, and connect the peer switches in a VLT domain to
an attached access device (switch or server).
Figure 53-11 and Figure 53-12 show a sample configuration of virtual link trunking on each VLT peer
switch.
Figure 53-13 shows how to verify the connection to a VLT domain from an attached switch.
FTOS_VLTpeer1# show spanning-tree rstp brief
Executing IEEE compatible Spanning Tree Protocol
Root ID Priority 0, Address 0001.e88a.dff8
Root Bridge hello time 2, max age 20, forward delay 15
Bridge ID Priority 4096, Address 0001.e88a.d656
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 200000 DIS 800 4096 0001.e88a.d656 128.2
Po 3 128.4 128 200000 DIS 800 4096 0001.e88a.d656 128.4
Po 4 128.5 128 200000 DIS 800 4096 0001.e88a.d656 128.5
Po 100 128.101 128 800 FWD(VLTi) 800 0 0001.e88a.dff8 128.101
Po 110 128.111 128 00 FWD(vlt) 800 4096 0001.e88a.d656 128.111
Po 111 128.112 128 200000 DIS(vlt) 800 4096 0001.e88a.d656 128.112
Po 120 128.121 128 2000 FWD(vlt) 800 4096 0001.e88a.d656 128.121
FTOS_VLTpeer2# show spanning-tree rstp brief
Executing IEEE compatible Spanning Tree Protocol
Root ID Priority 0, Address 0001.e88a.dff8
Root Bridge hello time 2, max age 20, forward delay 15
Bridge ID Priority 0, Address 0001.e88a.dff8
We are the root
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 200000 DIS 0 0 0001.e88a.dff8 128.2
Po 3 128.4 128 200000 DIS 0 0 0001.e88a.dff8 128.4
Po 4 128.5 128 200000 DIS 0 0 0001.e88a.dff8 128.5
Po 100 128.101 128 800 FWD(VLTi) 0 0 0001.e88a.dff8 128.101
Po 110 128.111 128 00 FWD(vlt) 0 0 0001.e88a.dff8 128.111
Po 111 128.112 128 200000 DIS(vlt) 0 0 0001.e88a.dff8 128.112
Po 120 128.121 128 2000 FWD(vlt) 0 0 0001.e88a.dff8 128.121
Displays the RSTP state of port channels in the VLT domain.
Port channel 100 is used in the VLT interconnect trunk
(VLTi) to connect to VLT peer2. Port channels 110, 111, and
120 are used to connect to access switches or servers (vlt).










