OS - Windows 2016 Server Datacenter, this is production server launched on AWS.
When did it begin and how often does it occur?
Issue started on 4th April after installing KB5000803. Issue is intermittent.
What errors do you see?
Application server (app is in asp.net) unable to reach SQL server with timeout error.
What's the environment and are there recent changes?
It is production server. There are no recent changes in environment.
What have you tried to troubleshoot this?
We have uninstalled the update and then it started working again as before update.
Then we have tried to replicate these servers to our DR site for testing purpose and installed the KB5000803 on them.
It worked at first attempt and we have stopped the servers. Again we have started the servers on next day for troubleshooting and we found that it stopped working without any changes with same timeout error as production.
We checked in the event logs but unable to see any error. Then we have just rebooted SQL server and it started working again.
So not sure what is the issue. Looks like issue is intermittent. Please advice the solution or let us know if any bug with this patch.