This is a follow up from question: AlwaysON Availability Groups - IP address change of secondary replica node
Same scenario, Availability Group in synchronous commit mode, one primary and one secondary replica in a multi-subnet configuration. The cluster nodes are physical machines. Due to hardware maintenance, the server used by the secondary replica cluster node is being moved, so will be offline and come back online with a different IP address in a different subnet. How would one approach this?
My initial thoughts are: If possible, add the new network interface to the secondary node. Configure the new network interface with the new IP address which is in a different subnet. The cluster should automatically build the internal routes and register the new network interface.
In FCM (Failover Cluster Manager) a new cluster network will appear under the 'Networks' tab. In cluster core resources, add the new network and create a new static IP address for the cluster VNN. Apply the changes then go back in and add an OR dependency on the new IP address.
Prior to the server move outage where the old IP address/network interface will be removed, in FCM, go back to cluster core resources, go into the properties of the cluster VNN and remove the old network/static IP address and remove any dependencies on it. When the server is taken offline and comes back online, the old network interface won't be visible to the server and won't appear in the networks tab in FCM. There shouldn't be any issues with any clustered resources as any dependencies on the old IP/subnet/network were removed.
Is there anything else that should be taken into consideration? Since the cluster nodes are physical, does this complicate matters with regards to the network interfaces? With testing in a virtual environment it's obviously simplified as removing and attaching virtual network switches is easy.