Mailing List Archive

From: "Thomas E. Dodd /CSDC" <ted@cypress.com>
I boot 2.2pre6 with a new CPU (686MX from 686).
First boot was fine. Went to Win9x to check new CPU,
fine. Reboot 2.2. Unable to mount /var (ext2fs on hdb2)
Ran fsck complained bad-super block. Ran with -b 8193,
fixed errors, mounted fine. Rebooted to check.
Failed to mount /var again. Now fsck, mount, and other
ext2fs utils say not a valid ext2fs, bad magic number.
I tried fsck again with trhe first 10 superblocks,
and get the same results.
Looking at results of 'dd if=/dev/hdb2 bs=1024'
the magic number is the same as a good ext2fs (0xEF53)
at same offset from begining of partition.
Any ideas what is wrong?
How to fix?
-Thomas
The way you present things here it sounds as if Win9x did
something to the superblock. That is possible, such things
have been seen before. But of course something else may
have been wrong, and the intermediate booting of Win9x
might not have had anything to do with these fs problems.
It is a pity that you did e2fsck. (My experience is that
when things are mildly broken, e2fsck fixes everything fine,
but when things are badly broken e2fsck makes things even worse.)
If there are no valuable data on this disk, so that you can play
with it, perhaps you could try to repeat the procedure?
Make a fresh ext2 filesystem on the same partition as before,
Save the partition table and the first 100 blocks or so of this
ext2 partition. Perform the same actions. Report reproducible
results.
My first conjecture would be that nothing is wrong with Win9x
[flames > /dev/null] but that your hardware is not 100% reliable -
maybe this new CPU was overclocked or so. If you get reproducible
problems, do these go away if you use a different CPU?
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/

Guest section DW wrote:
>
> From: "Thomas E. Dodd /CSDC" <ted@cypress.com>
>
> I boot 2.2pre6 with a new CPU (686MX from 686).
> First boot was fine. Went to Win9x to check new CPU,
> fine. Reboot 2.2. Unable to mount /var (ext2fs on hdb2)
> Ran fsck complained bad-super block. Ran with -b 8193,
> fixed errors, mounted fine. Rebooted to check.
>
> Failed to mount /var again. Now fsck, mount, and other
> ext2fs utils say not a valid ext2fs, bad magic number.
> I tried fsck again with trhe first 10 superblocks,
> and get the same results.
>
> Looking at results of 'dd if=/dev/hdb2 bs=1024'
> the magic number is the same as a good ext2fs (0xEF53)
> at same offset from begining of partition.
>
> Any ideas what is wrong?
> How to fix?
>
> -Thomas
>
> The way you present things here it sounds as if Win9x did
> something to the superblock. That is possible, such things
> have been seen before. But of course something else may
> have been wrong, and the intermediate booting of Win9x
> might not have had anything to do with these fs problems.
Windows doesn't see the drive or the partition, so it didn't
get to the filesystem.
> It is a pity that you did e2fsck. (My experience is that
> when things are mildly broken, e2fsck fixes everything fine,
> but when things are badly broken e2fsck makes things even worse.)
I thought it was mild:(
> If there are no valuable data on this disk, so that you can play
> with it, perhaps you could try to repeat the procedure?
> Make a fresh ext2 filesystem on the same partition as before,
> Save the partition table and the first 100 blocks or so of this
> ext2 partition. Perform the same actions. Report reproducible
> results.
It happened once befor on a different drive but still /var.
So I moved it. the other disk is still fine and this one
was before. I can't force it to happen at will, but it
has happened before.
> My first conjecture would be that nothing is wrong with Win9x
I agree
> maybe this new CPU was overclocked or so. If you get reproducible
> problems, do these go away if you use a different CPU?
No. The previous time was a different CPU.
Not overclocked.
I need a way to recover the data. I need the logs and info
for RPM. I don't have enough room to backup and reinstall,
then restore my changes.
Anyone know the ext2fs well enough to help?
-Thomas
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/

"Theodore Y. Ts'o" wrote:
>
> Date: Tue, 19 Jan 1999 13:28:42 -0600
> From: "Thomas E. Dodd /CSDC" <ted@cypress.com>
>
> Yes :) The fs is hosed now. And 2.0.36 won'r mount it either.
>
> Well, have you checked the partition table to make sure it's still sane?
> And can you do e2fsck -b 8193 with the CPU backed out?
>
Partition table is fine.
With either CPU fsck fails.
I tried the frist 10 superblocks (1,8193,16385,24577,...,81921)
all report not ext2fs.
-Thomas
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/