From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: with ECARTIS (v1.0.0; list xfs); Sat, 23 Dec 2006 20:06:28 -0800 (PST) Received: from s-utl01-dcpop.stsn.net (s-utl01-dcpop.stsn.net [72.255.0.201]) by oss.sgi.com (8.12.10/8.12.10/SuSE Linux 0.7) with SMTP id kBO46Lqx030511 for ; Sat, 23 Dec 2006 20:06:23 -0800 Message-ID: <458DF8F7.5030104@sandeen.net> Date: Sat, 23 Dec 2006 21:50:15 -0600 From: Eric Sandeen MIME-Version: 1.0 Subject: Re: unexpected XFS SB magic number References: <458C6719.6080106@sandeen.net> <458C6C5A.6090504@sandeen.net> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: xfs-bounce@oss.sgi.com Errors-to: xfs-bounce@oss.sgi.com List-Id: xfs To: gbakos@cfa.harvard.edu Cc: linux-xfs@oss.sgi.com Gaspar Bakos wrote: > Hi, Eric, > One of the users was running quite memory and disk IO intensive tasks > past week. This lead to a crash. (I was not around to keep an eye on > it). The computer rebooted, and few days later another crash, etc. > Finally, when I returned this week, I found it powered off. > > And then I realized that the sdc1 partition can not be mounted any more. Well, something put a gpt label on top of your xfs partition... and it wasn't xfs :) >> i also remember something about parted (maybe...) finding a backup gpt >> signature at the end of a disk, and "helpfully" copying it over the >> front end if so. This was a bug. sgi guys do you remember? > > But for this one has to invoke parted, and commit the operations done, > am I right? if I recall, even invoking parted could do this. > Maybe there is a nasty daemon doing something. The fs was also exported > as NFS and mounted by two other hosts. > > --------- > So the questions are: > - what partition type to choose next time? > - is there a simpler way of recovery (than xfs_recovery), i.e. the > first few bytes of the partition need to be changed back to something > XFS magic, and the rest is probably untouched? i'd google around and find out how big the gpt header is; try to find out how much of the front of your partition got clobbered. that'll give a clue as to how much you may have lost. -Eric