Failed to start /etc/rc.local Compatibility

If you see [FAILED] Failed to start /etc/rc.local Compatibility roll by on boot, then you need to check /etc/rc.local.

Check current status, should be fail and you should/could get a clue on what's wrong:

sudo systemctl status rc-local

Edit your /etc/rc.local file

Then try to start it again:

systemctl start rc-local