Ferdora Core 4 cannot read superblock

[Murphy Wong]

Dear all,

I've been using my Fedora Core 4 for months. Recently, after doing the
up2date, suddenly the machine panic and hang up there. When rebooting,
it keeps on saying "cannot read superblock". When I use "linux rescue",
I can only mount /dev/hda1 (/boot). The /dev/hda2 seems having problem.
When I do "fsck -f /dev/hda2", it says "bad magic number in
super-block while trying to open /dev/hda2" and ask me to do "e2fsck -b
8193 <device>". When I issue "e2fsck -b 8193 /dev/hda2", it keeps on
reporting "bad magic number in super-block". I've tried "-f" and it
doesn't work either. I cannot mount the file system or booting up the
system.

Do you have any clue? Thanks.

Regards,
Murphy

[Jean-David Beyer]

Murphy Wong wrote:
>
> Dear all,
>
> I've been using my Fedora Core 4 for months. Recently, after doing the
> up2date, suddenly the machine panic and hang up there. When rebooting,
> it keeps on saying "cannot read superblock". When I use "linux rescue",
> I can only mount /dev/hda1 (/boot). The /dev/hda2 seems having problem.
> When I do "fsck -f /dev/hda2", it says "bad magic number in super-block
> while trying to open /dev/hda2" and ask me to do "e2fsck -b 8193
> <device>". When I issue "e2fsck -b 8193 /dev/hda2", it keeps on
> reporting "bad magic number in super-block". I've tried "-f" and it
> doesn't work either. I cannot mount the file system or booting up the
> system.
>
> Do you have any clue? Thanks.
>
Chances are you will have to restore all of /dev/hda2 from your backup and
order a new hard drive before things get worse. This assumes you did not
screw up that partition yourself and running up2date was only a coincidence.

Notice first, though, that the backup superblocks are placed at regular
locations on the partition, but those locations may not be in multiples of
8192. I seem to recall that on my RHEL3 system, they are at multiples of
32768, but I tend to make quite large partitions, rarely less than 4 GBytes,
and sometimes a lot more. So try "e2fsck -b 32769 <device>" first.

--
.~. Jean-David Beyer Registered Linux User 85642.
/V\ PGP-Key: 9A2FC99A Registered Machine 241939.
/( )\ Shrewsbury, New Jersey http://counter.li.org
^^-^^ 05:00:00 up 20 days, 19:47, 4 users, load average: 4.15, 4.16, 4.17

[Robert Nichols]

In article <11sups8kephs405@corp.supernews.com>,
Jean-David Beyer <jdbeyer@exit109.com> wrote:
:
:Notice first, though, that the backup superblocks are placed at regular
:locations on the partition, but those locations may not be in multiples of
:8192. I seem to recall that on my RHEL3 system, they are at multiples of
:32768, but I tend to make quite large partitions, rarely less than 4 GBytes,
:and sometimes a lot more. So try "e2fsck -b 32769 <device>" first.

You can use mke2fs with the "-n" option to find the default locations
of the backup superblocks.

--
Bob Nichols AT comcast.net I am "RNichols42"

[General Schvantzkoph]

On Thu, 19 Jan 2006 12:48:36 +0800, Murphy Wong wrote:

>
> Dear all,
>
> I've been using my Fedora Core 4 for months. Recently, after doing the
> up2date, suddenly the machine panic and hang up there. When rebooting,
> it keeps on saying "cannot read superblock". When I use "linux rescue",
> I can only mount /dev/hda1 (/boot). The /dev/hda2 seems having problem.
> When I do "fsck -f /dev/hda2", it says "bad magic number in
> super-block while trying to open /dev/hda2" and ask me to do "e2fsck -b
> 8193 <device>". When I issue "e2fsck -b 8193 /dev/hda2", it keeps on
> reporting "bad magic number in super-block". I've tried "-f" and it
> doesn't work either. I cannot mount the file system or booting up the
> system.
>
> Do you have any clue? Thanks.
>
> Regards,
> Murphy

I suspect that your disk has died. Your disk manufacturer has a diagnostic
CD on their website which will allow you to examine the SMART status of
your drive. There are also Linux smart tools that can examine the SMART
status. There is a project that puts the Linux SMART tools on a floppy
which sounds convenient assuming your machine has a floppy drive,

http://smartlinux.sourceforge.net/

In article <pan.2006.01.19.16.34.58.973986@yahoo.com>,
General Schvantzkoph <schvantzkoph@yahoo.com> wrote:

>I suspect that your disk has died. Your disk manufacturer has a diagnostic
>CD on their website which will allow you to examine the SMART status of
>your drive.

But his /boot is on the same drive.