On Tue, 2010-08-31 at 18:48 +0100, Colin Watson wrote: > On Tue, Aug 31, 2010 at 05:27:59PM +0200, Svante R Signell wrote: > > As revealed lately booting to Windows can cause parts of grub > > overwritten by Windows programs. > > http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=550702 > > https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/441941 > > > > I think this happened to me after a Windows XP session. I didn't react > > too much then, since grub booted into Linux and then grub-pc was > > upgraded by a new version. Missing boot menu might be due to some > > program overwriting the "embedding area". Now I'm reluctant to boot to > > Windows until this problem is solved. The problems seen are similar as > > the Ubuntu bug: > > https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/601563 where no > > boot menu is shown at all, but Linux boots automatically. > > > > Pleas let me know if I can help in any way to find which program is > > overwriting grub. > > Can you provide the specific data I requested in my blog post? Namely: > > * Save the output of 'fdisk -lu' to a file. In this output, take note > of the start sector of the first partition (usually 63, but might > also be 2048 on recent installations, or occasionally something > else). If this is something other than 63, then replace 63 in the > following items with your number.
No problem to do this! > * Save the contents of the embedding area to a file (replace '/dev/sda' > with your disk device if it's something else): 'dd if=/dev/sda > of=sda.1 count=63' Same here. > * Do whatever you do to make GRUB unbootable (presumably starting > Windows), then boot into a recovery environment. Before you > reinstall GRUB, save the new contents of the embedding area to a > different file: 'dd if=/dev/sda of=sda.2 count=63' Here I will potentially get into problems. In case grub won't boot I need a Netboot or complete CD to recover grub. When running the Debian installation CDs even choosing recovery gives you a lot of choices before getting into a shell. Which CD to burn when running unstable? Is it written somewhere how to reach the recovery shell. What to do then: grub-install and update-grub2? What about install-mbr? > * Follow up with these three files (the output of 'fdisk -lu', and the > embedding area before and after making GRUB unbootable). Will do all the above when I know I can reinstall grub without problems. > Thanks, > -- To UNSUBSCRIBE, email to [email protected] with a subject of "unsubscribe". Trouble? Contact [email protected]
