Hi, I'm aware that oVirt uses Cobbler to setup and configure new images but is it also possible to create and configure a VM image and then use it as a "golden" image to create multiple copies? I'm thinking along the lines of using QCOW2's ability to create new COW images (qemu-img create -b) but referencing the common read-only "golden" image. If this is not currently possible are there any plans for this kind of functionality? Using Cobbler and kickstart is nice and all but sometimes you just want to configure a VM image on your desktop machine (say) by hand and then be able to clone it many times instead of writing and maintaining kickstart scripts. Obviously Windows installations particularly benefit from this approach. Also on an unrelated note is oVirt going to be part of the "Enterprise Virtualization Manager for Servers" mentioned in Redhat's recent press release? http://www.redhat.com/about/news/prarchive/2009/agenda.html If not where does oVirt fit into the big picture? Daire
Daire Byrne wrote:> Hi, > > I'm aware that oVirt uses Cobbler to setup and configure new images but > is it also possible to create and configure a VM image and then use it > as a "golden" image to create multiple copies? I'm thinking along the > lines of using QCOW2's ability to create new COW images (qemu-img > create -b) but referencing the common read-only "golden" image. If this > is not currently possible are there any plans for this kind of > functionality? Using Cobbler and kickstart is nice and all but > sometimes you just want to configure a VM image on your desktop machine > (say) by hand and then be able to clone it many times instead of > writing and maintaining kickstart scripts. Obviously Windows > installations particularly benefit from this approach.Cobbler can do this via the Cobbler image object. We don't have support for 'golden' images in oVirt Server yet, but it is certainly on the roadmap. Adding support for this should be relatively easy since most of the groundwork for adding this was done when we added support for using Cobbler ISO images. (Patches welcome, as always!) I also believe that libvirt functionality for snapshots would be required here as well, and I think that is already in libvirt so hopefully we should just be able to use that. Probably the most challenging piece would be modifying the db model to track the snapshots. (Scott you have any thoughts on this?)> Also on an unrelated note is oVirt going to be part of the "Enterprise > Virtualization Manager for Servers" mentioned in Redhat's recent press > release?oVirt is a project developing virtualization management technology on Fedora. As some parts of Fedora feed into RHEL, some parts of oVirt may feed into RHEL virtualization in the future. Thanks, Perry -- |=- Red Hat, Engineering, Emerging Technologies, Boston -=| |=- Email: pmyers at redhat.com -=| |=- Office: +1 412 474 3552 Mobile: +1 703 362 9622 -=| |=- GnuPG: E65E4F3D 88F9 F1C9 C2F3 1303 01FE 817C C5D2 8B91 E65E 4F3D -=|
Perry, ----- "Perry Myers" <pmyers at redhat.com> wrote:> > I'm aware that oVirt uses Cobbler to setup and configure new images but > > is it also possible to create and configure a VM image and then use it > > as a "golden" image to create multiple copies? I'm thinking along the > > lines of using QCOW2's ability to create new COW images (qemu-img > > create -b) but referencing the common read-only "golden" image. If this > > is not currently possible are there any plans for this kind of > > functionality? Using Cobbler and kickstart is nice and all but > > sometimes you just want to configure a VM image on your desktop machine > > (say) by hand and then be able to clone it many times instead of > > writing and maintaining kickstart scripts. Obviously Windows > > installations particularly benefit from this approach. > > Cobbler can do this via the Cobbler image object. We don't have > support for 'golden' images in oVirt Server yet, but it is certainly on the > roadmap. Adding support for this should be relatively easy since most > of the groundwork for adding this was done when we added support for > using Cobbler ISO images. (Patches welcome, as always!)Cool. Good to know - thanks.> I also believe that libvirt functionality for snapshots would be > required here as well, and I think that is already in libvirt so hopefully we > should just be able to use that. Probably the most challenging piece > would be modifying the db model to track the snapshots. (Scott you > have any thoughts on this?)I'm not too bothered about snapshotting running machines (although that would be cool too) so much as the initial creation of a COW image using the golden image as a common read-only base. Basically it would be great if oVirt could use all the qemu-img functionality.> > Also on an unrelated note is oVirt going to be part of the "Enterprise > > Virtualization Manager for Servers" mentioned in Redhat's recent press > > release? > > oVirt is a project developing virtualization management technology on > Fedora. As some parts of Fedora feed into RHEL, some parts of oVirt > may feed into RHEL virtualization in the future.Okay, thanks. Maybe the press release is talking more about the Qumranet solutions that were acquired. Are there plans to give oVirt the ability to schedule and migrate machines based on load etc. or will this be managed by a separate system (via libvirt)? Is oVirt only supposed to be used for used the initial provisioning? Regards, Daire
Cheers for the info. I like how oVirt is shaping up and will keep a close eye on your progress. When we it has a few more of our required features I will endeavour to contribute. Regards, Daire ----- "Hugh O. Brock" <hbrock at redhat.com> wrote:> On Thu, Feb 26, 2009 at 09:02:44PM -0500, Perry Myers wrote: > > Daire Byrne wrote: > >> Okay, thanks. Maybe the press release is talking more about the > >> Qumranet solutions that were acquired. Are there plans to give oVirt > >> the ability to schedule and migrate machines based on load etc. or will > >> this be managed by a separate system (via libvirt)? Is oVirt only > >> supposed to be used for used the initial provisioning? > > > > There are plans to provide migration based on load in oVirt. I don't > > think that'll be part of core libvirt, but it will be part of oVirt. > > oVirt is not just for initial provisioning. It's about managing the > > guest through it's entire lifecycle, monitoring it, tracking state and > > eventually neat things like chargeback. Hugh is heading up this effort, > > so I'll let him elaborate :) > > oVirt server, as part of the cloud management bits we are now building > into it, will be able to automatically migrate machines to guarantee > SLA (for example). I wouldn't expect to see that feature before ~6 > months from now however (although patches are, as always, welcome...)