[CentOS-virt] About doing backups with kvm guests

Wed Dec 16 18:23:37 UTC 2009
Kenni Lund <kenni at kelu.dk>

2009/12/16 ml at johestephan.de <ml at johestephan.de>:
> Hi all,
>
> As far as I know ist there no need to dd the hole disk. It should fit if you
> So just:
>
> - take the snap
> - mount it
> - pack it

Yep, but you'll not be able to restore it into a bootable system again
if you only backup the files. You could however, take a backup with dd
of the partitiontable+bootloader and then afterwards backup the files
of each partition.

On a restore you would then copy back the partitiontable+bootloader,
format the filesystems and copy the files back.

But comparing this hacky solution to just using qcow2 on top of a
Linux filsystem, the qcow2 solution seems much nicer :) Especially now
when the qcow2 performance has been highly optimized:
http://fedoraproject.org/wiki/Features/KVM_qcow2_Performance
https://rhn.redhat.com/errata/RHSA-2009-1659.html

Best Regards
Kenni Lund