From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [10.34.131.19] (dhcp131-19.brq.redhat.com [10.34.131.19]) by int-mx12.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id s559JqKN020905 for ; Thu, 5 Jun 2014 05:19:52 -0400 Message-ID: <53903637.5030800@redhat.com> Date: Thu, 05 Jun 2014 11:19:51 +0200 From: Zdenek Kabelac MIME-Version: 1.0 References: <1208338730.18211142.1401956193776.JavaMail.zimbra@redhat.com> <1862191909.18215030.1401956807760.JavaMail.zimbra@redhat.com> In-Reply-To: <1862191909.18215030.1401956807760.JavaMail.zimbra@redhat.com> Content-Transfer-Encoding: 7bit Subject: Re: [linux-lvm] File-system uuid on LVM snapshot Reply-To: LVM general discussion and development List-Id: LVM general discussion and development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , List-Id: Content-Type: text/plain; charset="us-ascii"; format="flowed" To: linux-lvm@redhat.com Dne 5.6.2014 10:26, Rajesh Joseph napsal(a): > Hi all, > > Origin volume and snapshot volume share the same file-system UUID. So after the snapshot we fix the uuid by running xfs_admin or tune2fs. > Do you have any recommendation or best practice in this regard? > With thin pools and thin volumes - snapshot of thin volume is now created 'inactive' and it's skipped from default activation (you could always override skip with -K i.e. : lvchange -ay -K vg/mythinsnap) So with thins you should mostly have only a single volume active with the FS UUID. If you happen to have multiple volumes active and you need to mount xfs filesystem - use 'nouuid' (and eventually norecovery for read-only activated snapshots) mount options. For old-snapshosts - all volumes need to be available/active - so you need to use 'nouuid' option always. I don't see much point in changing FS UUID on your snapshot - unless of course you plan to use snapshots as different volumes with just a 'single' starting point (i.e. preinstalled tree of files) Regards Zdenek