Comments on: LVM FYI http://pthree.org/2008/01/09/lvm-fyi/ Linux. GNU. Freedom. Sat, 30 Aug 2008 05:34:06 +0000 http://wordpress.org/?v=2.7-hemorrhage hourly 1 By: Tony Yarusso http://pthree.org/2008/01/09/lvm-fyi/#comment-88329 Tony Yarusso Wed, 09 Jan 2008 20:03:15 +0000 http://www.pthree.org/2008/01/09/lvm-fyi/#comment-88329 I've been trying to diligently do backups to avoid this sort of thing, but I've been disappointed in what's out there. However, sbackup ("Simple Backup Suite") is really close - all I ask is the addition of scp so that it can make use of passwordless SSH-key-enabled authentication rather than storing passwords in config files. I’ve been trying to diligently do backups to avoid this sort of thing, but I’ve been disappointed in what’s out there. However, sbackup (”Simple Backup Suite”) is really close - all I ask is the addition of scp so that it can make use of passwordless SSH-key-enabled authentication rather than storing passwords in config files.

]]> By: dbr http://pthree.org/2008/01/09/lvm-fyi/#comment-88307 dbr Wed, 09 Jan 2008 15:43:48 +0000 http://www.pthree.org/2008/01/09/lvm-fyi/#comment-88307 2/Serge van Ginderacht: It's as big a bug as rm -rf /, really. It just wipes the disc because you told it to create a LVM volume on that disc. One thing, although probably too late if you're installing stuff back over it. If you created a new partition on the disc, chances are you've not actually destroyed the data, just the refernces too it (I.e it's still on the disc) The author of the http://www.linux.com/articles/56588 article has more or less the same problem as you (wiped data accidently), and includes a fairly detail description of how he recovered the data. 2/Serge van Ginderacht:
It’s as big a bug as rm -rf /, really. It just wipes the disc because you told it to create a LVM volume on that disc.

One thing, although probably too late if you’re installing stuff back over it. If you created a new partition on the disc, chances are you’ve not actually destroyed the data, just the refernces too it (I.e it’s still on the disc)

The author of the http://www.linux.com/articles/56588 article has more or less the same problem as you (wiped data accidently), and includes a fairly detail description of how he recovered the data.

]]> By: Serge van Ginderacht http://pthree.org/2008/01/09/lvm-fyi/#comment-88291 Serge van Ginderacht Wed, 09 Jan 2008 10:09:24 +0000 http://www.pthree.org/2008/01/09/lvm-fyi/#comment-88291 Ouch, I read over the exact statements. Like Dennis says, 'pvcreate' only a diskpartition which is not in use yet :-) Ouch, I read over the exact statements. Like Dennis says, ‘pvcreate’ only a diskpartition which is not in use yet :-)

]]> By: Serge van Ginderacht http://pthree.org/2008/01/09/lvm-fyi/#comment-88290 Serge van Ginderacht Wed, 09 Jan 2008 10:04:02 +0000 http://www.pthree.org/2008/01/09/lvm-fyi/#comment-88290 Can you elaborate on what exactly happens? Is this a known bug? What is crashing exactly? The whole LVM system? The current volume group? thx Can you elaborate on what exactly happens? Is this a known bug? What is crashing exactly? The whole LVM system? The current volume group? thx

]]> By: Dennis Krul http://pthree.org/2008/01/09/lvm-fyi/#comment-88284 Dennis Krul Wed, 09 Jan 2008 09:35:28 +0000 http://www.pthree.org/2008/01/09/lvm-fyi/#comment-88284 Uhm.. If you want to create a logical volume you have to use the lvcreate command. The pvcreate command creates a physical volume. Only use pvcreate on empty disks! And then use vgcreate to create a volume group on it (or vgextend to extend an existing one). After that use lvcreate to create a logical volume on the volume group. That being said, in most cases you can recover from a broken LVM configuration. Boot from a rescue cd. Find your backups in /etc/lvm/backup and you can look up the disk id's and write them back to your physical disk using pvcreate --uuid [id-from-lvm-backup] /dev/disk. Then reactivate your volumegroup (vgchange -a y /dev/vgname) and mount your logical volumes like nothing happened. That is ofcourse a bit more complicated when /etc resides on the volume group you're trying to recover ;) Uhm.. If you want to create a logical volume you have to use the lvcreate command. The pvcreate command creates a physical volume.

Only use pvcreate on empty disks! And then use vgcreate to create a volume group on it (or vgextend to extend an existing one). After that use lvcreate to create a logical volume on the volume group.

That being said, in most cases you can recover from a broken LVM configuration. Boot from a rescue cd. Find your backups in /etc/lvm/backup and you can look up the disk id’s and write them back to your physical disk using pvcreate –uuid [id-from-lvm-backup] /dev/disk. Then reactivate your volumegroup (vgchange -a y /dev/vgname) and mount your logical volumes like nothing happened.

That is ofcourse a bit more complicated when /etc resides on the volume group you’re trying to recover ;)

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