- Show VLT status and configuration (active and standby) based on Figure 14 using the following command. The role for one switch in the VLT pair is primary and its peer switch is assigned to the secondary role. Ensure Peer-Routing is enabled.
S5248F-Leaf1# show vlt 127
Domain ID : 127
Unit ID : 1
Role : secondary
Version : 3.1
Local System MAC address : 0c:b0:ad:b2:00:00
Role priority : 32768
VLT MAC address : 0c:38:92:fa:00:00
IP address : fda5:74c8:b79e:1::1
Delay-Restore timer : 90 seconds
Peer-Routing : Enabled
Peer-Routing-Timeout timer : 0 seconds
Multicast peer-routing timer : 300 seconds
VLTi Link Status
port-channel1000 : up
VLT Peer Unit ID System MAC Address Status IP Address Version ----------------------------------------------------------------------------------
2 0c:38:92:fa:00:00 up fda5:74c8:b79e:1::2 3.1
This following command highlights configuration issues between VLT peers. Mismatch examples include incompatible VLT configuration settings, VLAN differences, different switch operating system versions and spanning-tree inconsistencies. There should be no mismatches reported on any switch configured for VLT. To resolve mismatches:
S5248F-Leaf1# show vlt 127 mismatch
VLT-MAC mismatch:
No mismatch
Peer-routing mismatch:
No mismatch
VLAN mismatch:
No mismatch
This following command is used to validate VLT LAG status on leaf switches. This command shows the status and active VLANs of all VLT LAGs (Port channel 10 in this example). The local and peer status must both be up.
S5248F-Leaf1# show vlt 127 vlt-port-detail
vlt-port-channel ID : 10
VLT Unit ID Port-Channel Status Configured ports Active ports
----------------------------------------------------------------
* 1 port-channel10 UP 1 1
2 port-channel10 UP 1 1
Show spanning-tree rstp brief
The following command validates that Spanning Tree Protocol is enabled on the leaf switches. All interfaces are forwarding (Sts column shows FWD). One of the leaf switches (S5248F-Leaf1 in this example) is the root bridge and sever-facing interfaces (PO10 in this example) are edge ports.
S5248F-Leaf1# show spanning-tree active
Spanning tree enabled protocol rstp with force-version rstp
Performing IEEE compatible Spanning Tree Protocol
Root ID Priority 0, Address 0cc8.6efa.0000
Root Bridge hello time 2, max age 20, forward delay 15
Bridge ID Priority 0, Address 0cc8.6efa.0000
We are the root
Configured hello time 2, max age 20, forward delay 15
Flush Interval 200 centi-sec, Flush Invocations 53
Flush Indication threshold 65535
Interface Designated
Name PortID Prio Cost Sts Cost Bridge ID PortID
----------------------------------------------------------------------------------
port-channel10 128.2674 128 400 FWD 0 0 0cc8.6efa.0000 128.2674
Interface
Name Role PortID Prio Cost Sts Cost Link-type Edge
----------------------------------------------------------------------------------
port-channel10 Desg 128.2674 128 400 FWD 0 AUTO No
Although VRRP is traditionally an active/standby protocol, where only one VRRP router does the forwarding at a time, when used between VLT peers, it becomes active/active. Even the backup VRRP router will forward packets for hosts and end devices.
S5248F-Leaf1# show vrrp brief
Interface Group Priority Prempt State Version Master addr(s) Virtual addr
----------------------------------------------------------------------------------
vlan50 IPv4 50 150 true master-state 3 172.16.1.1 172.16.1.254
S5248F-Leaf2# show vrrp brief
Interface Group Priority Prempt State Version Master addr(s) Virtual addr
----------------------------------------------------------------------------------
vlan50 IPv4 50 140 true backup-state 3 172.16.1.1 172.16.1.254
S5248F-Leaf1# show uplink-state-group detail
(Up): Interface up (Dwn): Interface down (Dis): Interface disabled (NA): Not Available
*: VLT Port-channel V: VLT Status L: Local Peer Operational Status ^: Tracking Status
Uplink State Group : 1 Status : Enable,up
Upstream Interfaces : Eth 1/1/53(Up) Eth 1/1/54(Up)
Downstream Interfaces: Po 10(Up)
Note: In VLT deployment with VRRP configuration, when used between VLT peers, it becomes active/active. Even the backup VRRP router will forward packets for hosts and end devices.
When the upstream Ethernet 1/1/53 and 1/1/54 on leaf1 are down, the downstream port in uplink-state-group 1 is disable with port channel 10 on Leaf 1.
S5248F-Leaf1# show uplink-state-group detail
(Up): Interface up (Dwn): Interface down (Dis): Interface disabled (NA): Not Available
*: VLT Port-channel V: VLT Status L: Local Peer Operational Status ^: Tracking Status
Uplink State Group : 1 Status : Enabled,down
Upstream Interfaces : Eth 1/1/53(Dwn) Eth 1/1/54(Dwn)
Downstream Interfaces: Po 10(Dis)
