Reassigning to grub2, which is the source package for grub-pc.
> The BOOT_IMAGE command defined root as - in my case - /dev/sdq2,
There is no "BOOT_IMAGE" variable anywhere is the standard grub configuration, so I have no idea what this refers to. And grub will only use /dev/sd* style device names for booting if you specify 'GRUB_DISABLE_LINUX_UUID=true' in /etc/default/grub.
Please attach your /etc/default/grub and /boot/grub/grub.cfg from the affected system.
Reassigning to grub2, which is the source package for grub-pc.
> The BOOT_IMAGE command defined root as - in my case - /dev/sdq2,
There is no "BOOT_IMAGE" variable anywhere is the standard grub configuration, so I have no idea what this refers to. And grub will only use /dev/sd* style device names for booting if you specify 'GRUB_DISABLE_ LINUX_UUID= true' in /etc/default/grub.
Please attach your /etc/default/grub and /boot/grub/grub.cfg from the affected system.