[SLUG] Migrating from LVM to a plain old disk

[James Linder <jam@xxxxxxxxx>]

On 15/04/2012, at 10:00 AM, slug-request@xxxxxxxxxxx wrote:

> I want to migrate away from a LVM Volume Group (2 disks) to a single
> plain old disk (500G).
> 
> Back story: A couple years I thought I might have to learn about LVM.
> So I created a Volume Group using the Debian installer and have never
> done anything else.
> 
> My ideal solution (I think) is if there is a device I can `dd` from,
> and I can just set the destination disk as a non LVM'd disk.
> 
> Some output:
> # vgdisplay
> File descriptor 4 (/dev/urandom) leaked on vgdisplay invocation.
> Parent PID 4932: bash
>  --- Volume group ---
>  VG Name               erupt
>  System ID
>  Format                lvm2
>  Metadata Areas        2
>  Metadata Sequence No  4
>  VG Access             read/write
>  VG Status             resizable
>  MAX LV                0
>  Cur LV                3
>  Open LV               2
>  Max PV                0
>  Cur PV                2
>  Act PV                2
>  VG Size               146.71 GiB
>  PE Size               4.00 MiB
>  Total PE              37557
>  Alloc PE / Size       37557 / 146.71 GiB
>  Free  PE / Size       0 / 0
>  VG UUID               hrlysx-65nB-56Yt-VwUv-cC5O-wJIr-vjz4Jx
> 
> # pvscan
> File descriptor 4 (/dev/urandom) leaked on pvscan invocation. Parent
> PID 4932: bash
>  PV /dev/sdb2   VG erupt   lvm2 [36.79 GiB / 0    free]
>  PV /dev/sdc2   VG erupt   lvm2 [109.92 GiB / 0    free]
>  Total: 2 [146.71 GiB] / in use: 2 [146.71 GiB] / in no VG: 0 [0   ]
> 
> Is this asking to much?

Without shadow of doubt dd will fail.
(dd must have the same format to work ie same number of blocks, same partition table etc)

find . (or cat list, whatever) | cpio -pdv > /tothe/newdisk
reinstall grub/lilo

James