Comment 23 for bug 1463120

I've tested this with kernel 4.10-rc3 in a local VirtualBox VM (Ubuntu Server 16.04), with the same fstab error as above, and am able to confirm most of the symptoms described by the reporter.

When attempting to 'mount -a', it presents the expected "wrong filesystem type" error, but doesn't render the system unresponsive. Upon reboot, however, it drops into a maintenance console without presenting an error about a failed mount attempt. Consequently, the server would be unreachable for maintenance via SSH.

'journalctl -xb' provides a log that contains an error about the failed mount attempt, but doesn't point to it as the reason for dropping into a maintenance terminal, and it isn't the last thing logged.

After fixing fstab (which requires physical access) and rebooting ('reboot' from the maintenance console), GRUB does still have a countdown, but it starts around 10 seconds, instead of 3 seconds (~3 seconds is the default for Ubuntu Server). Otherwise, at this point, the system is able to boot up automatically, without issue.

After rebooting a second time (from the normal BASH prompt), the GRUB countdown is back to ~3 seconds, and the system boots normally (automatically), from there.

Thanks, again, for helping to resolve this bug.