[Linux-cluster] Unformatting a GFS cluster disk

[DRand at amnesty.org]

Hi, 

We're making some progress on recovering our GFS disk..

We've created a small c app, which marked all bytes as 0xff on:

grp hdr: with offset 80
grp blk: with offset 120

But fsck takes ages to run (looks like weeks on our full disk). If we run 
on a smaller disk the process completes faster but after that, device is 
non mountable.

So, we're thinking about an alternate strategy. What if we try and 
reconstruct the GFS headers to tell it where old file group structures are 
located. ie. I can identity all (old and new) filegroups on the disk. I 
then change the header structures so they point to the old file groups (at 
least the ones that were not overwritten by the previous mkfs) rather than 
the new file groups. 

Does this approach make sense? Where do I update the GFS headers to tell 
the system where the old file group headers are located? 

Damon.
Working to protect human rights worldwide

DISCLAIMER
Internet communications are not secure and therefore Amnesty International Ltd does not accept legal responsibility for the contents of this message. If you are not the intended recipient you must not disclose or rely on the information in this e-mail. Any views or opinions presented are solely those of the author and do not necessarily represent those of Amnesty International Ltd unless specifically stated. Electronic communications including email might be monitored by Amnesty International Ltd. for operational or business reasons.

This message has been scanned for viruses by Postini.
www.postini.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://listman.redhat.com/archives/linux-cluster/attachments/20080331/1c0124b6/attachment.htm>