From mboxrd@z Thu Jan  1 00:00:00 1970
Date: Fri, 6 Jan 2017 13:04:32 -0600
From: David Teigland <teigland@redhat.com>
Message-ID: <20170106190432.GA22165@redhat.com>
References: <ea995d2fb8e2be94ab44e870c88a5be8@xenhideout.nl>
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In-Reply-To: <ea995d2fb8e2be94ab44e870c88a5be8@xenhideout.nl>
Subject: Re: [linux-lvm] duplicate pv change uuid
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To: Xen <list@xenhideout.nl>
Cc: Linux lvm <linux-lvm@redhat.com>

On Fri, Jan 06, 2017 at 07:55:53PM +0100, Xen wrote:
> I want to ask again,
> 
> How can I change the UUID of a duplicated PV?
> 
> I mirrored a partition to another disk and tried to change its UUID with
> pvchange -u.
> 
> But I think LVM had already decided to replace the reference to the PV
> (partition) on the old disk by the reference to the new disk, or something.
> 
> For some reason it always prefers the wrong one.
> 
> Now I booted with just one disk but I cannot change the UUID of the running
> system, but if I connect the other disk I am afraid I won't be able to
> change it also.
> 
> How does one do this, again?

vgimportclone is meant to do this.  It strategically uses filters to
isolate and modify the intended devs.