os-prober fails to find OSes on uncleanly-unmounted filesystems

[Vadim Peretokin]

Binary package hint: grub

I have Maverick installed on /dev/sda1, and the GRUB configuration entry listed it as Ubuntu blah blah (on /dev/sda1). After yesterday's update, that entry is gone now, and only Natty's entry is available. The partition is still there though and is accessible from within Natty.

ProblemType: Bug
DistroRelease: Ubuntu 11.04
Package: grub (not installed)
ProcVersionSignature: Ubuntu 2.6.38-5.32-generic 2.6.38-rc6
Uname: Linux 2.6.38-5-generic x86_64
NonfreeKernelModules: nvidia
Architecture: amd64
Date: Fri Mar 11 07:54:42 2011
EcryptfsInUse: Yes
InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Alpha amd64 (20110302)
ProcEnviron:
 LANGUAGE=en_CA:en
 LANG=en_CA.UTF-8
 SHELL=/bin/bash
SourcePackage: grub
UpgradeStatus: Upgraded to natty on 2011-03-09 (2 days ago)

[Colin Watson (cjwatson)]

This was probably because your Maverick system's root filesystem wasn't cleanly unmounted. This is a known issue in os-prober. If you mount and unmount the Maverick filesystem from Natty then run 'sudo update-grub', that should restore it.

[Vadim Peretokin (vperetokin)]

Ah, thanks for the tip. I did shut Natty down properly, but it does have a rather peculiar shutdown screen with text all over the screen. update-grub did list Maverick, so thank you very much for the quick response!

[Colin Watson (cjwatson)]

I'd forgotten about bug 683355 - I'll make this a duplicate of it.