Starts emergency mode for failed "auto" fstab mounts (not marked with nofail)

[bzipitidoo]

Problem is with systemd, or with how the installation configured systemd.

Machine is a 64bit system, AMD CPU and graphics card, dual boot. Windows 8.1 is on sda1 and 2, and Lubuntu 15.04 is on sda5 (swap), 6 (/), and 7 (/home). I installed Windows first. During install of Lubuntu, I added sda2 to the list of partitions to mount during boot. I chose /mnt/windows for the mount point.

Windows 8.1 defaults to this Fast Startup in which instead of doing a real shutdown, it hibernates the partition, not cleanly unmounting it. After booting Windows then rebooting and choosing Ubuntu, the system does not bring up the GUI, instead dropping to a text screen, saying:

ACPI PCC probe failed.
starting version 219.
welcome to emergency mode....

The only error in the logs is that the system can't mount /mnt/windows. Those other messages about ACPI and version 219 are red herrings. I don't know why systemd is configured to think that /mnt/windows is critical to the system, and why it responds by refusing to run the GUI (staying in runlevel 1 maybe?).

After changing Windows to disable its Fast Startup and then booting into Lubuntu, the system works normally and LXDE comes up as expected.

[Martin Pitt (pitti)]

Adding "nofail" to the /etc/fstab entry for /mnt/windows will make the system boot again for you, if you expect breakage there and having /mnt/windows is not essential for your system.

All mounts with "auto" but not "nofail" are considered essential for the system to boot, as everything else would just be heuristics and guesswork.

[bzipitidoo (bzipitidoo)]

"nofail" sounds like a good option.

Should also mention that Windows could still create or have a hibernation file even when Fast Startup is disabled. I added "remove_hiberfile" to the options for /mnt/windows in /etc/fstab to work around that problem. That works for me, but some users may want to use hibernation in Windows.