How to fix two disks with the same Volume Group?

[Da Rock]

On Thu, 2008-03-20 at 08:48 +0000, Chris G wrote:
> I have just had Fedora 7 re-installed on my work desktop as the old
> disk drive was slowly failing.
> 
> I need to access the old disk if I can, it's still in the system and
> visible but the person who installed it didn't change volume groups so
> I have two disk drives with the same volume group.  How do I change the
> name of the old disk's volume group so I can mount it and see it?
> 
> Running vgscan returns:-
> 
>   Reading all physical volumes.  This may take a while...
>   WARNING: Duplicate VG name VolGroup00: Existing
> P6sqp0-rIos-JYmi-8L32-ymtN-LzB4-g5BdLL (created here) takes precedence
> over TdWFKp-H4tw-UrVq-Jmre-26hv-zmyE-IZXQLI
>   Found volume group "VolGroup00" using metadata type lvm2
>   Found volume group "VolGroup00" using metadata type lvm2
> 
> -- 
> Chris Green
> 

Actually its a real pain the ***. Bee there, done that. For future
reference- when installing change the name of the fs to the machine
name. Saves these sorts of issues, I found this out the hard way and
came across this gem on the net.

Forgive me for going into a taboo area, but the way I fixed it (vgrename
won't work in this case I reckon- please try though) was to throw an
Ubuntu live disk in the cdrom and boot, download lvm2 from the Ubuntu
repo (Debian won't work- although if Debian make a live disk then use
their repo). Run update software and run the vgrename from there. If you
need root password then (it seems a little redundant but anyway... it
works for me...) go to administration and users and change the root
password there.

Seeing you can't have both disks with the same name at the same time,
you'll need to change the name of your current disk. If you reboot it
will fail once you've renamed, so make sure you change your grub, init
file, and mount your main lvm partition and change your inittab file to
match your new name.

This is very involved, I know, so ensure you have an instruction web
page up there to follow from. Run a google search on how to use Ubuntu
to rectify an lvm. If you find the right one, it'll have all the
instructions you need- except for the inittab: found that out the hard
way. If you don't fix that, you get a selinux error and it won't boot
properly.

Good luck