Upstart (mountall job) waits indefinitely for devices making boot process hang

[Marcin Krol]

After upgrading one of my machines from 14.04 to 16.04 and switching back to upstart the system stopped booting. It turned out that after initramfs inovokes /sbin/init system hangs on mountall job waiting indefinitely for LVM devices to appear.

Problem affects all 16.04 installations (both 14.04 upgrades or fresh ones) where LVM devices are included in /etc/fstab. Below are example log entries that are filling /var/log/upstart/mountall.log when "init=/sbin/upstart --debug" is added to kernel command line:

try_mount: /var/lib/postgresql waiting for device
try_mount: /var/spool/bacula waiting for device
try_mount: UUID=886c73fd-8392-4361-956e-9cda47b0eb65 waiting for device

My system is:

Description: Ubuntu 16.04.2 LTS
Release: 16.04

All devices in fstab are referenced by UUIDs.

To workaround the problem simple script executing "lvm vgchange -ay" must be created and placed in /etc/initramfs-tools/scripts/local-top

Problem doesn't exist when using systemd.

[Marcin Krol (hawq)]

Bug is more generic. Basically if some device listed in /etc/fstab is not available mountall job will hang forever. Example:

1. System has root crypted with password
2. All LVM volumes are on disk crypted with key file placed on root device
3. fstab contains references to LVM volumes

Result:

1. Systems asks for root device password and it is successfully mounted
2. System doesn't decrypt disk with LVM volumes
3. LVM volumes are not available so mountall hangs and systemd doesn't boot

As previously, this can be fixed with simple script in /etc/initramfs-tools/scripts/local-bottom that decrypts LVM disk and issues lvm vgchange -ay. Again, problem doesn't exist when using systemd.

[Marcin Krol (hawq)]

In above comment 3. in Result should say "system doesn't boot" not "systemd doesn't boot" :)