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From: Gionatan Danti <g.danti@assyoma.it>
Message-ID: <5735AEE4.4080402@assyoma.it>
Date: Fri, 13 May 2016 12:39:32 +0200
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Subject: [linux-lvm] Backup superblock for thin provision?
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To: LVM general discussion and development <linux-lvm@redhat.com>

Hi all,
using thin provisioning in production machines (using it mostly for its 
fast snapshot support, rather than for thin provision / storage 
overcommit by itself), I wonder what to do if a critical metadata 
corruption, as the loss of the superblock, should happen.

Filesystems generally have some backup copy of the superblock; should 
the primary one fail, another copy can be used.

So I have the following questions:
- how about thin LVM? Has it a backup superblock somewhere?
- how can the metadata be reliable backupped without shutting down the 
volume?
- more generally, how to deal with metadata backup? Does vgcfgrestore 
works for thin volumes?

Thank you all.

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