This morning my application could not connect my MySQL master instance in Google Cloud SQL. The master instance does not have more logs, but the replication instance log show that the replication could not connect to the master too.
I tried to restart MySQL, but an hour later, it didn't start.
What should I do?
There are several possible reasons for this issue. For instance, your master instance may have failed due to an error while a dump was being created, or the instance may have been under maintenance and now it cannot restart correctly, etc. If that were the case, you would need to get in touch with Google Cloud Platform Support to have your Cloud SQL instance manually restarted.
Alternatively, you can also check the documentation for instance connection issues and how to diagnose issues in connections.
If nothing of this applies to your case, you should consider adding more information to your question, since there could be a problem with the expiration of your SSL server certificate, with the Proxy, etc.
