I have a new SQL 2019 failover cluster which consists of two nodes and two SQL instances. The first instance is using port 1433 and the second 1439.
During failover testing I have been having issues with the second instance. It moves across to the new node and all cluster resources are brought online and are healthy. There are no events in the logs. I can connect to the instance on the server directly but remote connections fail.
If I move it back to the original node it works fine again.
Th first instance appears to be unaffected and works fine on both nodes.
Does anyone have any suggestions on what I can check/try?