On Tue, Apr 17, 2012 at 10:00 AM, Juha Kallio <[email protected]> wrote: > On 17.4.2012 2:00, Jordan Uggla wrote: >> >> On Mon, Apr 16, 2012 at 9:42 AM, Juha Kallio<[email protected]> >> wrote: >>> >>> Hello! >>> >>> I have migrated to grub2 from grub-legacy, and have had a working >>> installation in a virtual machine for a while. Today I updated the Debian >>> wheezy installation, and now grub-install to /dev/vda fails with the >>> following error: >>> >>> /usr/sbin/grub-setup: warn: Attempting to install GRUB to a disk with >>> multiple partition labels or both partition label and filesystem. This >>> is >>> not supported yet.. >>> /usr/sbin/grub-setup: warn: Embedding is not possible. GRUB can only be >>> installed in this setup by using blocklists. However, blocklists are >>> UNRELIABLE and their use is discouraged.. >>> /usr/sbin/grub-setup: error: will not proceed with blocklists. >>> >>> This is a virtio disk from KVM, and should only have a basic partition >>> table >>> that was created on install. fdisk -l /dev/vda confirms that with the >>> following information: >>> >>> Disk /dev/vda: 6442 MB, 6442450944 bytes >>> 16 heads, 63 sectors/track, 12483 cylinders, total 12582912 sectors >>> Units = sectors of 1 * 512 = 512 bytes >>> Sector size (logical/physical): 512 bytes / 512 bytes >>> I/O size (minimum/optimal): 512 bytes / 512 bytes >>> Disk identifier: 0x000d70a5 >>> >>> Device Boot Start End Blocks Id System >>> /dev/vda1 * 2048 8386559 4192256 83 Linux >>> >>> I haven't tried to boot this virtual machine yet. I also haven't tried >>> the >>> --force flag, since I shouldn't be restricted to using blocklists. I can >>> grub-install to another device, /dev/sda, but for some reason the actual >>> boot device doesn't work anymore as a target for grub-install. >>> >>> I'm sorry if this problem would be more suited to Debian mailing lists. >>> >>> Regards, >>> Juha Kallio >>> >>> _______________________________________________ >>> Help-grub mailing list >>> [email protected] >>> https://lists.gnu.org/mailman/listinfo/help-grub >> >> Please post the output of "sudo parted -l" >> > > Sorry for not reporting this earlier, but I solved the problem already. > After thinking about the error message, I remembered that when installing > the virtual machine, I first tried to install it without partitioning > /dev/vda. The disk actually had both a partition label and a filesystem, I > just thought that I had overwritten the filesystem by creating the partition > table. > > To clarify, what I did when I installed the VM was: > > 1) I created an ext4 filesystem on /dev/vda, and tried to install Debian on > it. > 2) Naturally I couldn't complete the install, because there was no room for > GRUB anywhere. Stupid me. > 3) After realizing my error, I started the install from scratch, and this > time I created a partition table on /dev/vda. (At this point, I thought the > filesystem on /dev/vda would be completely overwritten.) > 4) With the partition table, there was room for GRUB in the beginning of the > disk, and the install completed without errors. > > THE FIX: To get grub-install working again, I overwrote the first MB of > /dev/vda with zeroes, and restored the partition table. Now grub-install > completes without errors. What still puzzles me is why didn't I get the same > complaint from grub-install on my successfull install? And could there > actually be a _functioning_ ext4 filesystem and a partition table on the > same location? If it's impossible, why does grub try to detect it?
Yes, it is entirely possible to have a functioning ext4 filesystem and a partition table in its first sector as ext4 (like most filesystems) does not use this first sector so that it's available for a boot record (and so that something that tries to write a boot record doesn't clobber the FS). Having such a situation is however a very good way to lose data. > > > Regards, > Juha Kallio > > _______________________________________________ > Help-grub mailing list > [email protected] > https://lists.gnu.org/mailman/listinfo/help-grub _______________________________________________ Help-grub mailing list [email protected] https://lists.gnu.org/mailman/listinfo/help-grub
