[ale] Recovering PV/LVG without /etc/lvm/archive/file.vg

[Phil Turmel]

Probably.

Copies of the LVM metadata that you find in /etc/ also get written to 
part of the PV, near the beginning.  If you hex dump the first several 
megabytes you should find it.

( I've recovered from similar boo-boos this way.  You may find the 
offset for that backup documented somewhere. )

On 6/19/24 20:59, David Jackson via Ale wrote:
> The subject says it.  I was installing a new drive and installing a fresh
> OS onto the new drive, then transporting the old files over to the new
> drive and OS (ie, /home/dsj)
> 
> I had booted from an archlinux ISO, was doing a manual partition.  But then
> I made a boo boo with the new Logical Volume Group and wanted to blow it
> away to start over.
> 
> My new system was on nvme1n1 and I blew away the PV and LV info for nvme0n1
> which contained the PV/LV  info for all my previous data.  Very sad senior
> moment!
> 
> Now, since I booted from an arch ISO usb stick, the /etc/lvm/archive files
> were in volatile memory, so I don't have a copy of them.  When I load up my
> new system, which I eventually installed just fine (I'm writing this email
> from that system), everything works great.  But I'd like to recover the old
> system (that's probably still on nvme0n1 in the second partition, When I
> boot from the new system on nvme1n1, I can look in /dev/disk/by-uuid/ and
> see the old PV for nvme0n1 uuid I think:
> 2f1aede8-a033-4ec4-8c9f-290d7a7c3458
> 
> But there's no record for LVs or PVs on nvme0n1 anywhere in
> /etc/lvm/archive.
> 
> Also, whenever I install Arch, I use a script that auto creates the same PV
> and LV specs on the target drive.  The partition sizes won't have changed.
> 
> (Pretty much all the googling I've read assumes that a /etc/lvm/archive/
> filename.vg exists somewhere. )
> 
> Is there any way I can restore the PV/LVG info on nvme0n1 with what I have
> available?  Without the archive file?
> 
> Thanks!
> 
> Dave