If the peer node fails, the peer-routing-timeout command enables the availability of peer routing features. It retains the corresponding local destination MAC address until the timer expires. For customers who would like to be aware of the node failure and its associated traffic, the peer-routing-timeout command would cease routing on behalf of the peer after the timer's expiration. This timer does not need to be configured for standard, high-availability requirement deployments.
The delay-restore timer command has a default value of 90 seconds. After a VLTi flap or node reboot, the VLT port-channel is held in a down state in the secondary VLT node until the delay-restore time has passed. This function allows the MAC and ARP address table synchronization to complete between the nodes and the control protocols to converge before reinstating the VLT port-channel for forwarding the traffic. When the VLT port-channel is brought to a working state, the forwarding tables are populated in the hardware, allowing traffic to flow without disruption. In a highly scaled setup, it is recommended that the timer is increased to ensure that all of the tables are synchronized, and that the protocol converges before opening the VLT port-channel to avoid traffic issues.