Incomplete migration from 20.5 to 21 – shared MariaDB MySQL



Hi everyone, 
2 days ago my Android boxes have started to upgrade from Kodi 20.5 to Kodi 21. 
First box got stuck on initial screen after DB migration
Day after, the 2nd box did not try to migrate and stayed stuck on initial screen

story continues at bottom, however the working workaround for my case is just below. Maybe that might help others !
Apparently, the main issue was some kind of timeout occuring during migration. Maybe at box level.
The steps are

  • delete the incomplete and incorrect myvideos_xbmc131 and MyMusic 83 database
  • plugged an USB fake mouse dongle which does nothing more than moving randomly the mouse ensuring the screensaver (or other stuff) not to start. 

That has worked for me. 
Obviously it was not a migration error but rather a kind of time out

Story and details
Suspecting a migration issue, I deleted the myvideos_xbmc131 and MyMusic 83, then restarted one box.
Same issue.
In my case, on all the box, after a while a kind of screensaver do start. Thus leading to never know how far I was. After having wait quite long, I hit an arrow button on the remote. Instead of being on Kodi, I was back to the box initial screen
Doing that multiple times, I started to suspect a kind of timeout or memory shortage doing a shutdown of Kodi.
Not motivated to retrieve the log, I tried to blindly avoid the screensaver. One option could have been to plug a mouse and move regularly. However I was not motivated to do this for 1/2H or more. So I did plug an USB fake mouse dongle which does nothing more than randomly and constantly the mouse on the screen thus avoiding the screensaver

In my case it has work. The migration completed successfully, Kodi did bring the main screen and everything was working.

Maybe that could help someone

Good luck

ps: I still have other issues in parallel on one of my windows PCs. There is a thread opened for it at 377308 (thread) No clue yet how this one will ends