Plex falls offline, doesn't crash PMS.exe

Error 503 is indicative of a deadlock and requests queuing up and then when we reach over 4000 queued unactioned requests we start to return error 503

For deadlocks one would need a Plex Media Server process dump and logs zip and list of all the connections at the time of the deadlock.

I see you are running on windows, so should be fairly easy to get a process dump. Please make sure the server remains on the latest version

See the following for diagnostics

Diagnostics for a deadlock / lockout (Windows)

  1. Prepare yourself by finding server security token string as it will be needed to get the list of connections at the time of the lockout, see this support article https://support.plex.tv/articles/204059436-finding-an-authentication-token-x-plex-token/
  2. When the problem occurs (and please wait for sufficient time before capturing diagnostics or restarting eg 10 minutes of requests to the server not getting through) , get the output from a specific browser request directly on the server. In a browser, go to this url http://localhost:32400/connections?X-Plex-Token=xxxxxxxxxxxxxxxxxxxxx where you put the server token string instead of the xxxxxxxxxxxxxxxx. Copy the displayed output to a text file and save and note down the exact time when the request response was returned
  3. Next is to force a process dump for the Plex Media Server.exe process. We can do this with Windows Task Manager. Find the Plex Media Server.exe process, select it and right click on it and choose Create Dump
  4. Check that the dmp file has been created
  5. Restart the server and capture the zipped logs
  6. Zip the dmp files and upload to dropbox or similar service
  7. send me by private message link to the zipped dmp files and send the saved /connections output text files and the zipped logs