On Sat, Aug 15, 2015 at 01:22:42PM +1200, Daniel Reurich wrote:
> On 15/08/15 13:13, Hendrik Boom wrote:
> >On Sat, Aug 15, 2015 at 12:41:06PM +1200, Daniel Reurich wrote:
> >>On 15/08/15 12:24, Hendrik Boom wrote:
> >>>I tried plugging a external hard drive into my newly installed Devuan
> >>>system, and immediately ran into a problem: It seems the volume group
> >>>name used on that drive is the same as the one on my devuan system.
> >>>Not that surprising; thee external drive contains the Debian system I'm
> >>>migrating away from.
> >>>
> >>>lvdisplay tells me:
> >>>
> >>>root@notlookedfor:~# lvdisplay
> >>> WARNING: Duplicate VG name VG1: Existing
> >>>zXs7iy-ukO4-ecrC-B1ag-wQkA-6L4K-YKyKRV (created here) takes precedence
> >>>over P4Ggic-hQS6-b82V-zUj6-a0eu-dA3z-5mIkOH
> >>> WARNING: Duplicate VG name VG1: Existing
> >>>P4Ggic-hQS6-b82V-zUj6-a0eu-dA3z-5mIkOH (created here) takes precedence
> >>>over zXs7iy-ukO4-ecrC-B1ag-wQkA-6L4K-YKyKRV
> >>> WARNING: Duplicate VG name VG1: Existing
> >>>zXs7iy-ukO4-ecrC-B1ag-wQkA-6L4K-YKyKRV (created here) takes precedence
> >>>over P4Ggic-hQS6-b82V-zUj6-a0eu-dA3z-5mIkOH
> >>>
> >>>
> >>>How do I go about mounting its LVM partitions without screing everything
> >>>up? Can I just ignore the name conflict and mount by UUID? And are the
> >>>UUIDs in the error message the ones I need for this?
> >>
> >>>
> >>>Or is there some way to rename VG1 to something else? Some way that
> >>>will take care of all the corner cases? There's a command vgimportclone
> >>>that seems to be for this, but ... it says it also changes the UUID's,
> >>>which are *not* duplicates, and it just might be that another use of
> >>>this external disk might rely on those particulat UUIDs.
> >>
> >>vgrename supports identifying the volumegroup by UUID - so try:
> >>vgrename <UUID> <new vg name>
> >
> >I'll have to be careful with that -- the lvdisplay message suggests that
> >it has assigned new UUID's for that VG1 at least three times. Does
> >that mean the disk has been rewritten? Or does LVM lie to itself as a
> >kludge to prevent catastrophe?
>
> Use vgdisplay and pvdisplay to determine which UUID belongs to which
> system/disk
> >
> >>
> >>If your changing the old vg and not booting it again, then fine, but
> >>if you want to change either the running systems VG name (or keep
> >>the old system bootable) you'll need to fix the relevant fstab and
> >>grub(2) configuration to match the changes.

Easy enough to edit /boot/grub/grub.cfg.
Or do I really have to edit other files that this is made from? I
remember there was some complication there with Debian's grub2.

> >
> >Yes. I hope that's all.
>
> Don't forget to do `update-initramfs -u -k all` and `update-grub` to
> rebuild the
> >
> >It may ne simples to rename the VG1 in the devuan system -- if something
> >goes wrong, I don't yet have enough effort invested to make a fresh
> >install problematic.
> >
> If you do that you shouldn't have too much trouble as Devuan should
> be using the UUID's of the logical volumes anyway.
> >>>
> >>>It's just possible that the LVM partition names will also have a
> >>>conflict.
> >>
> >>shouldn't be a problem once you fix the volume group name conflict.
> >
> >Yes, their full names do end up containing the VG name, don't they?
>
> Yup
> >>

> >>Cheers,
> >>    Daniel.

> >
> >Thank you. You've been very helpful.
> >
> Your welcome - all part of the service.
>

> Cheers,    
>     Daniel
> -- 
> Daniel Reurich
> Centurion Computer Technology (2005) Ltd.
> 021 797 722