complete fs corruption after fsck

[Matija Nalis]

On Fri, Aug 06, 2010 at 11:21:47AM +0200, Udo Rader wrote:
> What I desperatly need is at least one of the many +400M backup files
> located on the server. They happen to be so called postsgresql "custom"
> dump files, identifyable by their "PGDMP" file header.

They are probably too big to be in one piece on the disk, and since the
pgdump custom format does not sound like something easily detectable as
correct (it looks like it's usually gzip compressed, which means it would
look like random data), they probably won't recover correctly.

> On the other hand, if I fgrep the qcow2 image file for the string, I get
> results soon.
> 
> So, are there any options left to get more data back? I've played with
> lde [1], but I must admit that the magic required to understand lde is
> beyond my level of magic ...

You can try one of the following: 

http://www.cgsecurity.org/wiki/TestDisk
http://www.itu.dk/people/jobr/magicrescue/
http://www.sleuthkit.org/
http://www.keldix.com/keld/readme-salvage.html

or some of the tools from:
https://ext4.wiki.kernel.org/index.php/Undeletion

you would want to make a copy of qcow2 image first, as some of the tools
will damage it even more than it was in the beginning, so you want to start
with fresh copy on each try.

Good luck...

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