[ILUG] partition problem

[Padraig Brady]

Lennon, Conor wrote:

>Hi,
>
>I have a hard which has a damaged partition table.
>There's a linux partition on the disk and I know where the partition begins
>and ends.
>
First of all, for those that don't know gpart is great
for getting this information.

>
>I can do 
>	dd if=/dev/hdb of=/tmp/disk skip=<start> count=<length>
>The problem is that the partition is around 2.4 gigs, and dd stops after 2
>gigs, as linux doesn't support files bigger than that.
>I can mount the incomplete output file in loop back mode, but obviously not
>all the files are there.
>Is there any way to access all the files?
>
Hmm you could get around using a filesystem and
spit it directly onto an appropriately setup partition
on another disk.

If you want to put it on a filesystem and mount it
loopback you obviously need Large file support.
See http://www.suse.de/~aj/linux_lfs.html for overview
info. This is a bit out of date now though, and I understood
that this had all been fixed with new kernels/glibc? What
kernel/glibc are you using? FYI very new info about ext2
limits is summarised in the following graph:

http://www.cs.uml.edu/~acahalan/linux/ext2.gif

 <http://www.cs.uml.edu/%7Eacahalan/linux/ext2.gif>

I just did the following (glibc 2.1.3, kernel 2.4.0-ac4,
dd (GNU fileutils) 4.0l):
dd if=/dev/zero of=~/temp.bin count=6000000
and it worked fine. However (I think since I only
have glibc 2.1.3) mount gave the error "File to large"
when trying to mount it loopback. Actually anything
that tried to stat the file gave errors (ls etc.).

I wonder could you get around all this messing and
mount directly using:

mount -t ext2 -o loop,offset=<start> /dev/hdb mount-dir

Padraig.