If you have a SQL Server Availability Group (AG) and the VMs are being replicated to a disaster recovery site (cloud or on-prem), chances are the networking topology is not the same at the second site. These replication technologies can include VM replication, SAN LUN replication, or replicating server-level backups to the second site. It is quite complex to have the same network subnet existing at both sites, so usually, the secondary site contains a different networking subnet structure. It means that the servers being brought up at the secondary site are going to receive different IP addresses.
The Availability Group architecture, especially with its dependency on the Windows Server Failover Cluster (WSFC) layer, are quite intolerant of having these IP addresses changed. The utilities performing the failover might not even be aware of the WSFC-specific components that need to be adjusted.
Click through to see what you can do.