[libvirt-users] Transient VM Usage

[Kashyap Chamarthy]

On Fri, Sep 11, 2015 at 04:03:20PM +0200, Michal Privoznik wrote:
> On 11.09.2015 11:34, Mcburn wrote:
> > Hey at all,
> > 
> > my Name is Jens-Uwe Sperling. Iám a young student in computer science.
> > I want install a VM for testing at home.
> > 
> > i had install a VM with virt-install and the default parameters. (Number
> > cpu, mem etc.)
> > 
> > After that i install my OS and configure it.
> > 
> > Now i want work on this image in a transient way.
> > So i can use the OS with the given config but every change i do from now
> > should not change my image.
> > 
> > I found three ways to do that:
> > 
> >   -  Make a snapshot from my image and kill the snapshot after using.
> 
> Yes, this will work perfectly.
> 
> >   -  Using the transient option in the xml file under disk.
> 
> Wow, I didn't even know we have such element.
> 
> >   -  Making a qcow2 image and run that.
> 
> You mean copy the original image and run from that copy?
> 
> The first option has advantage, that you can save the progress or drop
> it if you don't like it. I mean, you'll create a snapshot, and then
> continue using the guest. As time moves on, you may find out that you
> actually want the state to be persistent, so you merge the active layer
> into the base. If not, then just drop it. 

Related notes on what Michal is talking about:

    http://wiki.libvirt.org/page/Live-disk-backup-with-active-blockcommit#Procedure


> With option #2 you don't have this opportunity.  Option #3 is like #1
> except that you're doing the snapshot yourself :)

-- 
/kashyap