whoops, corrupted my filesystem

[pnkflyd51]

Hi all-

I corrupted my filesystem by not doing a RTFM first... I got an automated email that the process monitoring the SMART data from my hard drive detected a bad sector. Not thinking (or RTFMing), I did a fsck on my partition- which is the main partition. Now it appears that I've ruined the superblock.

I am running Fedora Core 6. I am booting off the Fedora Core 6 Rescue CD in order to try to fix things (my system isn't bootable.)

Doing a e2fsck /dev/hda2 tells me that the superblock is corrupt. When I do a mke2fs -n /dev/hda2, it tells me that other backups are stored on 32768, 98304, 16840, 229376, 294912, 819200, 884736, 1605632, 265???? (cut off), 4096000, 7962624, 11239424, 20480000, 23887872.

When I try doing a e2fsck -b xxx /dev/hda2, on any of the superblocks <= 4096000 I get the message that it's corrupted. When I do >= 7962625, I get "Invalid argument while trying to open /dev/hda2."

By the way, there's some sort of weird Logical Volume thing going on with this partition. On an old (out of date unfortunately) backup, the mtab file has it listed as /dev/mapper/VolGroup00-LogVol00. Perhaps this partition can't be addressed as /dev/hda2 and it should be addressed differently??

Should I try a mke2fs -S on this drive or is there something else I should try first? Everything I've read says to back up before mke2fs -S ing. I have an external ext3 drive with enough space to hold this mangled partition on it, although it currently has a single ext3 partition. Is there a way to copy the contents of the mangaled partition to the external ext3 partition w/o deleting what's already on it or resizing it and creating a 2nd partition?

If it is suggested that I try a mke2fs -S, how does that work? mke2fs -n tells me that:

Block size=4096 (log=2)
Fragment size=4096 (log=2)
30523392 inodes, 61022902 blocks
3051145 blocks
First data block=0
Maximum filesystem blocsk=0
1863 block groups
32768 blocks per group, 32768 fragments per group
16384 inodes per group

Thanks much for any help! I'd love to recover this instead of having to rebuild my linux PC!

AL


ps- This is a 250 GB Parallel ATA drive.

[pnkflyd51]

After reading up on LVM stuff, I have no idea just what I have done to my partition. I did a fsck /dev/hda2 while being in full interactive mode with the filesystem- now I know that's a big no-no. When booted off the Fedora Rescue CD, apparently LVM volumes are supposed to be in /dev/mapper and mine aren't. Anyone know how to try to get them to show up? I found out that to run the LVM2 tools from the Fedora Rescue CD, I need to do 'lvm.static <command>' like 'lvm.static lvdisplay'. The volumes show there, but I don't know what to try to do on them.

Anyone know of a good LVM2 FAQ Howto or Wiki? Or what I may have done to my LVM volumes by running a fsck /dev/hda2 ??

Thanks again, AL

[Dies]

Sorry, not familiar with LVM since I avoid them, so I can't really help out other than saying that it sounds like this would be a good time to have KNOPPIX and Gparted Live CD laying around.

[Iron_Mike]

Boot to runlevel 1 and type:

umount /
umount /boot
fsck -f -p

If it is really borked it might get a msgs about running in manual mode, in that case use:

fsck -f

and answer yes to everything it asks and cross your fingers.....

[pnkflyd51]

I figured out how to make the LVM volume accessable via a "lvm vgchange -a y" command from the Fedora Core 6 Rescue CD.

I've run e2fsck on /dev/mapper/VolGroup00-LogVol00 and it gives me multiple
"Block bitmap for group 0 is not in group. (block XXXXXX) Relocate<y>?". I
select y (actually, I ran with automatic mode.) This doesn't seem to help matters. When I rerun e2fsck, I get the same errors on the same blocks. And when I try to boot, I the partition is still unreadable.

Thanks for your help! Andy