Dell MX9116n EMC SmartFabric OS10 User Guide Release 10.5.1 - Page 1412

Peer 2 OS10(config)# interface ethernet 1/1/1 OS10(conf-if-eth1/1/1)# no switchport OS10(conf-if-eth1/1/1)# exit OS10(config)# interface ethernet 1/1/2 OS10(conf-if-eth1/1/2)# no switchport OS10(conf-if-eth1/1/2)# exit OS10(config)# vlt-domain 1 OS10(conf-vlt-1)# discovery-interface ethernet1/1/1-1/1/2 Configure the VLT MAC address You can manually configure the VLT MAC address. Configure the same VLT MAC address on both the VLT peer switches to avoid any unpredictable behavior during a VLT failover. For example, when a unit is down or when the VLTi is reset. If you do not configure a VLT MAC address, the MAC address of the primary peer is used as the VLT MAC address across all peers. Use the vlt-mac mac-address to configure the MAC address in both the VLT peers. Example configuration: OS10(config)# vlt-domain 1 OS10(conf-vlt-1)# vlt-mac 00:00:00:00:00:02 NOTE: Dell EMC Networking recommends configuring the VLT MAC address manually on both the VLT peer switches. Use the same MAC address on both peers. Configure the delay restore timer When the secondary VLT node boots, it waits for a pre-configured amount of time (delay restore) to restore the VLT port status. This delay enables VLT peers to complete the control data information exchange. If the peer VLT device was up at the time the VLTi link failed, the system delays bringing up the VLT ports after reload or peerlink restoration between the VLT peer switches. When both the VLT peers are up and running, and if the VLTi fails with the VLT heartbeat up, the secondary peer brings down the VLT ports. When the VLTi comes up, the secondary peer does not bring up its VLT ports immediately. The VLT ports are brought up only after the VLT port restoration timer expires. The delay restore timer enables both VLT peers to synchronize the control information with each other. The default timer is 90 seconds. You can use the delay-restore seconds command to modify the duration of the timer. Example: OS10(config)# vlt-domain 1 OS10(conf-vlt-1)# delay-restore 100 Configure the VLT peer liveliness check The VLT peer liveliness mechanism checks for the availability of the peer node. The system sends periodic keep-alive messages to detect the liveliness of the peer node. You must use a different link other than the VLTi for the peer liveliness check. This link is referred to as the VLT backup link. NOTE: Dell EMC Networking recommends using the OOB management network connection for the VLT backup link. If the VLTi goes down, the backup link helps to differentiate the VLTi link failure from a peer node failure. If all links in the VLTi fail, the VLT nodes exchange node liveliness information through the backup link. Based on the node liveliness information: ● If only the VLTi link fails, but the peer is alive, the secondary VLT peer shuts down its VLT ports. ● If the primary VLT node fails, both the VLTi and heartbeat fail, and the current secondary peer takes over the primary role. 1412 Virtual Link Trunking