Hi there! I made a dumb but serious error: I have a 500G external usb disk with a zfs-pool containing only this one disk. I then installed a new OS on my host-computer (debian with zfs-fuse) and wanted to access my usb-drive again. I know now that ZFS saves the pool-data on the filesystem - but then i thought it is saved on the host. So I tried to create a new pool (zpool create datahaven /dev/sda1) ... you know the rest - the existing pool is now overriden with a new, empty pool. Now my question: is there any way to get my (really important and of course not backed up ^^) files back? hope you can help a insightful dork, Andrew -- This message posted from opensolaris.org
On Sun, Sep 7, 2008 at 10:00 PM, Andrew <awiesi at gmail.com> wrote:> Hi there! > > I made a dumb but serious error: > > I have a 500G external usb disk with a zfs-pool containing only this one > disk. I then installed a new OS on my host-computer (debian with zfs-fuse) > and wanted to access my usb-drive again. I know now that ZFS saves the > pool-data on the filesystem - but then i thought it is saved on the host. So > I tried to create a new pool (zpool create datahaven /dev/sda1) ... you know > the rest - the existing pool is now overriden with a new, empty pool. > > Now my question: is there any way to get my (really important and of course > not backed up ^^) files back? > > hope you can help a insightful dork, Andrew > <http://mail.opensolaris.org/mailman/listinfo/zfs-discuss> >Nothing, not to the best of my knowledge. Note: zfs-fuse is out of date quite a bit and does not understand current zpools and zfs datasets. -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://mail.opensolaris.org/pipermail/zfs-discuss/attachments/20080908/fac4d32d/attachment.html>
Andrew wrote:> Hi there! > > I made a dumb but serious error: > > I have a 500G external usb disk with a zfs-pool containing only this > one disk. I then installed a new OS on my host-computer (debian with > zfs-fuse) and wanted to access my usb-drive again. I know now that > ZFS saves the pool-data on the filesystem - but then i thought it is > saved on the host. So I tried to create a new pool (zpool create > datahaven /dev/sda1) ... you know the rest - the existing pool is now > overriden with a new, empty pool. > > Now my question: is there any way to get my (really important and of > course not backed up ^^) files back?It''s going to be rather difficult. The problem is that when you create pool, all four labels are initialized, so all pointers to MOS are gone. This severely complicates things. In order to access your data (most of which is probably still there, except the parts that have beem overwritten by pool creation) you need to find at least one pointer to MOS object of the pool, which is hard. With this pointer it should be relatively easy to reconstruct appropriate uberblock. This post http://www.opensolaris.org/jive/thread.jspa?messageID=230052#230052 outlines possible approach for the hard part. Hth, Victor
wow, ok - i read the linked posts, but i''m not that fond of zfs and C anymore, so it will take some time to get myself uptodate and code this. luckily it''s not that timesensitive, i''ll work on it after my dayjob and keep this thread updated with my progress. thanks so far for the pointers and your help, andrew -- This message posted from opensolaris.org
Hi Andrew, On Dom, 2008-09-07 at 13:00 -0700, Andrew wrote:> I made a dumb but serious error: > > I have a 500G external usb disk with a zfs-pool containing only this > one disk. I then installed a new OS on my host-computer (debian with > zfs-fuse) and wanted to access my usb-drive again. I know now that ZFS > saves the pool-data on the filesystem - but then i thought it is saved > on the host. So I tried to create a new pool (zpool create datahaven > /dev/sda1) ... you know the rest - the existing pool is now overriden > with a new, empty pool.Actually, this is also partly my fault.. zfs-fuse should have warned you that /dev/sda1 was part of an existing pool.. sorry about that! As Victor said, now it''ll be rather difficult to get the data back.. I will release zfs-fuse 0.5.0 soon with updated ZFS code, and with a fix for this bug. Best regards, Ricardo
On Fri, Sep 12, 2008 at 1:33 AM, Ricardo M. Correia < Ricardo.M.Correia at sun.com> wrote:> > I will release zfs-fuse 0.5.0 soon with updated ZFS code, and with a fix > for this bug. >Ricardo, you are my hero (for today, at least) Please would you be so kind as to post announcements of your updates somewhere - just say where and I will subscribe to the list -- Any sufficiently advanced technology is indistinguishable from magic. Arthur C. Clarke Afrikaanse Stap Website: http://www.bloukous.co.za My blog: http://initialprogramload.blogspot.com ICQ = 193944626, YahooIM = johan_hartzenberg, GoogleTalk jhartzen at gmail.com, AIM = JohanHartzenberg -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://mail.opensolaris.org/pipermail/zfs-discuss/attachments/20080914/133c484b/attachment.html>
Hi Johan, On Dom, 2008-09-14 at 12:30 +0200, Johan Hartzenberg wrote:> > Please would you be so kind as to post announcements of your updates > somewhere - just say where and I will subscribe to the listI do post announcements on the zfs-fuse blog: http://zfs-on-fuse.blogspot.com/ You can subscribe to the RSS feed there. HTH, Ricardo