mounting a gzipped imagefile

cov · 10-14-2008, 09:42 AM

Hi,

I have piped a copy of a laptop's partition (XP, NTFS) onto a 40Gig partition through gzip using dd.

The (compressed) laptop partition now takes up 68% of my 40Gig partition.

What I want to do is to mount the imagefile so that I can try to recover deleted files.

Has anyone here done this? I have seen comments on google that indicate that it is not possible to mount compressed files. However, that information might be outdated. But if this is the case, is it possible to uncompress sections of the imagefile and mount those?

pinniped · 10-15-2008, 02:26 AM

You can uncompress the entire file and mount it (DON'T mount r/w); it doesn't make sense to uncompress sections because there is no predicting where the next block of data for a file is located. Better still, don't mount it - just use recovery tools to scan the uncompressed file.

cov · 10-15-2008, 03:02 AM

Quote:

Originally Posted by pinniped

You can uncompress the entire file and mount it (DON'T mount r/w); it doesn't make sense to uncompress sections because there is no predicting where the next block of data for a file is located. Better still, don't mount it - just use recovery tools to scan the uncompressed file.

Yeah. I thought that might be the case.

The problem is that I've got nowhere to uncompress it to.

theYinYeti · 10-15-2008, 03:29 AM

You could try and use Gnome VFS or similar to "mount" the archive, using gnomevfs-mount (something like: gnomevfs-mount /path/to/image.gz/#gzip:/ /mount/point1/), and then mount the file /mount/point1/image using loopback (something like: mount -o loop /mount/point1/image /mount/point2/).
I think it will perform very slowly though, or even freeze the computer, and you'll probably have to be root for the second command at least.

Yves.

cov · 10-15-2008, 03:36 AM

Quote:

Originally Posted by theYinYeti

You could try and use Gnome VFS or similar to "mount" the archive, using gnomevfs-mount (something like: gnomevfs-mount /path/to/image.gz/#gzip:/ /mount/point1/), and then mount the file /mount/point1/image using loopback (something like: mount -o loop /mount/point1/image /mount/point2/).
I think it will perform very slowly though, or even freeze the computer, and you'll probably have to be root for the second command at least.

Yves.

Hi Yves.

I don't appear to have 'gnomevfs-mount'. I have 'gnomevfs-mkdir', 'gnomevfs-monitor' and 'gnomevfs-mv'. What package is it part of?

theYinYeti · 10-15-2008, 06:26 AM

It depends on your distribution. For me, that's:

Code:

[yves@localhost ~]$ rpm -qf "$(which gnomevfs-mount)"
gnomevfs-mount-0.2.0-3mdv2007.1

Ultimately, you can get it there:
http://gnomedesktop.org/node/1981/31756

You could be interested in this article too:
http://en.wikipedia.org/wiki/GVFS

Yves.

theYinYeti · 10-15-2008, 06:45 AM

Unfortunately, gnomevfs-mount home page seems to have disapeared… Maybe you could get it from rpmbone or rpmfind, or some similar apt-related server.

Yves.

cov · 10-15-2008, 06:56 AM

Hi Yves.

My distro is Ubuntu (Hardy). I'm also using a live version of Helix which is also based on Ubuntu.

I've tried following the links you provided: the gnomedesktop.org link has a submission by 'tigrux' on 'gnome VFS Mount 0.1' but which links only to 404s.

The GVFS wiki refers to GVFS replacing gnomevfs, but doesn't seem to impart much information beyond that (it says it is a 'stub').

I've tried 'apt-get install gvfs' and I get the response that 'gvfs is already the newest version', so it must already be installed.

I'm not sure of where to go from here.

Thanks for your time.

Dave

cov · 10-15-2008, 07:13 AM

Yves, sorry, that last 'Thanks for your time' sort of sounds like I'm giving up.

I've opened my synaptic package manager and selected everything that looks like it might be something to do with gnomevfs and am installing it.

I have also located an rpm of gnomevfs-mount and will look at compiling it.

cov · 10-15-2008, 07:17 AM

Ah!

I now have 'gvfs-mount'. I'll give it a go!

cov · 10-15-2008, 07:22 AM

I'm not really having too much success at this.

gvfs doesn't seem to have a man page.

I've tried this

Code:

 sudo gvfs-mount /mnt/recover/imagefile /mnt/loop1
Error mounting location: volume doesn't implement mount
Error mounting location: volume doesn't implement mount

cov · 10-16-2008, 09:12 AM

Does anyone have any idea about how to use gvfs-mount?

Specifically to loop-mount a conpressed partition?

theYinYeti · 10-16-2008, 11:49 AM

I don't know anything about gvfs-mount, but a simple --help seems to indicate it has less features than gnomevfs-mount. Anyway, I found the bellow link, and it seems you don't have to give the mount point because it is auto-created in $HOME/.gvfs/:
http://www.galipe.net/articles/gvfs-...e-de-commande/

Yves.

cov · 10-16-2008, 03:10 PM

Thanks Yves,

I still get the same error.

There doesn't appear to be any information on the 'net about it (apart from that piece in french which only seems to deal with a network) and there's no man page.

Does anyone know of any recovery tools that would let me examine the file without decompressing it.

cov · 10-23-2008, 03:57 AM

Yves,

I'm still pursuing this. I have managed to install gnome-mount from an rpm I found.

Code:

gnome-mount /mnt/sda4/imagefile.gz /mnt/loop

does not generate an error, but /mnt/loop is not mounted.

I also tried the following with the same result:

Code:

gnome-mount /mnt/sda4/imagefile.gz/#gzip:/ /mnt/loop

Many thanks,

Dave