Bug#586815: grub-probe: error: cannot find a device for / is still a problem with dmcrypt, lvm2 and /dev/sda

[Michael Ostermeier]

Package: grub-pc
Version: 1.98-1

Hello,

congratulations to Albin (#542425), but the problem is still valid
for me.

I am running Debian testing with everything up to date (eccept the
kernel, which i cannot use due to this bug).

It all started a few days ago after an apt-get update.
Since that time, grub shows no background-picture on boot (which is no
problem for me) and update-grub doesnt work:

“# update-grub
/usr/sbin/grub-probe: error: cannot find a device for / (is /dev
mounted?).”

Yes, surely it is. Look here:
“# cat /proc/mounts 
rootfs / rootfs rw 0 0
none /sys sysfs rw,nosuid,nodev,noexec,relatime 0 0
none /proc proc rw,nosuid,nodev,noexec,relatime 0 0
none /dev devtmpfs rw,relatime,size=508048k,nr_inodes=127012,mode=755 0
0
none /dev/pts devpts
rw,nosuid,noexec,relatime,gid=5,mode=620,ptmxmode=000 0 0 
/dev/mapper/Taschenrechner-root / ext3
rw,relatime,errors=remount-ro,data=ordered 0 0 
tmpfs /lib/init/rw tmpfs rw,nosuid,relatime,mode=755 0 0 
tmpfs /dev/shm tmpfs rw,nosuid,nodev,relatime 0 0 
/dev/sda1 /boot ext2 rw,relatime,errors=continue 0 0 
/dev/dm-3 /home ext3 rw,relatime,errors=continue,data=ordered 0 0
fusectl /sys/fs/fuse/connections fusectl rw,relatime 0 0”

I ran # apt-get remove linux-image-2.6.26-2-686
and got (german environment):
“(Lese Datenbank ... 172972 Dateien und Verzeichnisse sind derzeit
installiert.) Entferne linux-image-2.6.26-2-686 ...
Running postrm hook script /usr/sbin/update-grub.
/usr/sbin/grub-probe: error: cannot find a device for / (is /dev
mounted?). User postrm hook script [/usr/sbin/update-grub] exited with
value 1 Examining /etc/kernel/postrm.d .
run-parts: executing /etc/kernel/postrm.d/initramfs-tools
2.6.26-2-686 /boot/vmlinuz-2.6.26-2-686 Richte grub-pc ein (1.98-1) ...
/usr/sbin/grub-probe: error: cannot stat `/dev/hda'.
Invalid device `/dev/hda'.
Try `/usr/sbin/grub-setup --help' for more information.
/usr/sbin/grub-probe: error: cannot find a device for / (is /dev
mounted?). dpkg: Fehler beim Bearbeiten von grub-pc (--configure):
 Unterprozess installiertes post-installation-Skript gab den Fehlerwert
1 zurück Fehler traten auf beim Bearbeiten von:
 grub-pc
E: Sub-process /usr/bin/dpkg returned an error code (1)
A package failed to install.  Trying to recover:
Richte grub-pc ein (1.98-1) ...
/usr/sbin/grub-probe: error: cannot stat `/dev/hda'.
Invalid device `/dev/hda'.
Try `/usr/sbin/grub-setup --help' for more information.
/usr/sbin/grub-probe: error: cannot find a device for / (is /dev
mounted?). dpkg: Fehler beim Bearbeiten von grub-pc (--configure):
 Unterprozess installiertes post-installation-Skript gab den Fehlerwert
1 zurück Fehler traten auf beim Bearbeiten von:
 grub-pc“

So you can install kernel after kernel, but none of them will be
displayed in the grub2 menu.

And for whatever reason /dev/hda has moved to /dev/sda on my system.

What i tried but didnt help is:

1 # echo change > /sys/block/dm-X/uevent (with all dm-[0-3])

2 I manually edited /boot/grub/device.map to contain sda instead of hda
  and did
  # grub-setup --device-map=/boot/grub/device.map /dev/sda

It both made no difference.

Please tell me, how to provide more details.

Best Regards
Miche

PS: Is there a way to get grub2 running or should i return back to good
old grub “legacy” which never hurted me and is easily configurable?