Re: [fedora-virt] What version did Live Snapshots get introduced in?

[Eric Blake]

On 10/09/2013 02:52 PM, Scott Baker wrote:
>  What version do I need to support live snapshots? I'm seeing:
>  
>  virsh snapshot-create-as Test123 snapshot1 "before yum upgrade"
>  --disk-only --atomic 
Non-live internal snapshots have been around for a long time (qemu 0.11?
and somewhere in the libvirt 0.8.x timeframe) - but that requires not
using the --disk-only option.

Live internal snapshots are a future possibility (it looks like qemu 1.7
will be adding 'blockdev-snapshot-internal-sync') - but libvirt will
have to be taught to use it, so that won't be any sooner than libvirt
1.1.4, and more likely several months out.

External snapshots (ie. using --disk-only) have always been live; and
requires 'blockdev-snapshot-sync', introduced in qemu 0.14; --atomic
requires 'transaction', introduced in qemu 1.1.  External snapshots in
libvirt require libvirt 0.9.5 for disk-only, or libvirt 1.0.5 for memory
alongside the disk snapshot.

Of course, various distros have backported some of these features onto
builds that report earlier version numbers, so sometimes you just have
to try it and see if it has been backported.

-- 
Eric Blake   eblake redhat com    [phone]
Libvirt virtualization library http://libvirt.org