I have a 3-node FCI: 1 primary / 1 secondary co-located in same data center on same subnet, and 1 secondary in a DR data center on another subnet.
Periodically, the virtual IP (VIP) for the AG name flips to the DR site and clients can't connect the Primary site. The quick fix is to remove the listener from the node in failover cluster manager, then remove the DNS entry that points to the DR site from AD.
I've checked most SQL and Windows logs and I can't find anything related to this. In fact, the AG doesn't actually flip to the DR site; it's just the DNS entry that gets updated with the incorrect IP for the DR server.
Has anyone else experienced this? I have 13 AGs, on a 9 node cluster, and only 2 AGs have experienced this. One of those I tore down and completely rebuilt with a new IP on the AG listeners, but the issue returned a week or two later.
Thanks for any help or info!