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From: Gionatan Danti <g.danti@assyoma.it>
To: Mike Snitzer <snitzer@redhat.com>
Cc: LVM general discussion and development <linux-lvm@redhat.com>
Subject: Re: [linux-lvm] Backup superblock for thin provision?
Date: Tue, 17 May 2016 15:18:11 +0200	[thread overview]
Message-ID: <573B1A13.7050006@assyoma.it> (raw)
In-Reply-To: <20160516185518.GA3320@redhat.com>



On 16/05/2016 20:55, Mike Snitzer wrote:
>
> There is more to the thinp metadata than just the metadata superblock.
>
> The DM thin-pool's metadata device was purposely split out from the data
> device to allow for additional metadata fault protection using RAID.
>
> I'll defer to the LVM developers for if/how LVM can be used to have
> thinp metadata redundancy even if you don't have multiple devices to be
> able to use a conventional RAID device.
>

Sure - I'm using thinp on a RAID6 volume, with two disks redundancy.

But what about an user error, or a lvm-related bug, which invalidate the 
superblock? In this case, RAID is of no help. On the other side, a 
superblock backup copy can be used to restore the system without major 
data loss.

More in general, how do you deal with metadata backups?
Thanks.

-- 
Danti Gionatan
Supporto Tecnico
Assyoma S.r.l. - www.assyoma.it
email: g.danti@assyoma.it - info@assyoma.it
GPG public key ID: FF5F32A8

      parent reply	other threads:[~2016-05-17 13:18 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-05-13 10:39 [linux-lvm] Backup superblock for thin provision? Gionatan Danti
2016-05-16 18:55 ` Mike Snitzer
2016-05-17  9:10   ` Zdenek Kabelac
2016-05-17 13:22     ` Gionatan Danti
2016-05-17 13:18   ` Gionatan Danti [this message]

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