Re: [linux-lvm] LVM1 -> LVM2 with failed disk

[BUCHMULLER Norbert <norbi.lists@nix.hu>]

Hi All!

On Thu, 20 Oct 2005 16:43:41 -0400
Erik Karlin <e_karlin@yahoo.com> wrote:

> Of course, one of my disks died. In the past, I used the -P partial flag
> to get the lvm to start so I could copy off my data from the "good" pv,
> but under lvm10, I don't see that option.
> 
> What are my options. Can I upgrade from lvm10 to lvm2 with a failed
> disk. The lvm doesn't start and while I can pvdisplay /dev/hda4 I cannot
> vgdisplay or lvdisplay (obviously) since the vg isn't starting.
> 
> Can I put in a dummy drive, somehow tell lvm to pvcreate a pv on the new
> drive with the same ID and then get the vg to come up?

This latter option worked for me once. The VG's name is "vg0", the died PV
was /dev/hdc1.

* Read the exact size of the died PV:

vgcfgrestore -ll -n vg0

* Add a new disk to the system, create a partition with _exactly_ the same
size as the died PV. (It need not be on the same device as the old PV, eg.
I'll call it /dev/hdb2.)

* Restore the LVM headers of the died PV onto the new disk:

vgcfgrestore -n vg0 -o /dev/hdb2 /dev/hdc1

* Rescan, activate the VG:

vgscan; vgchange -a y vg0

Hope it will help.


norbi