Since a few days ago our Azure installation has been throwing this error: A network-related or instance-specific error occurred while establishing a connection to SQL Server.

The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: TCP Provider, error: 0 - An attempt was made to access a socket in a way forbidden by its access permissions.)

We have three sites on the same resource and they are all behaving this way so I believe it has something to do with Azure resources. According to some online forums it is due to port exhaustion. However at this point I'm not sure how to fix this problem, and secondly how to prevent this from happening again.

We are running on Rock 5.2 and have been on this configuration for 6 months now without any issue. The only recent change we have made to the setup is move to use mailgun api instead of simple SMTP for email. We haven't done any bulk emails since the switch however so I'm not sure if that is even the problem.

Any clues are appreciated. Thanks.