How do I make delta clones ? OVM (aka Xen) vs Ovirt
Hi all, I'm new to Ovirt coming from a OVM ( aka Xen ) environment and I'm trying to work out how to do similar things. In my OVM environment I have VMs that are 100GB in size. These VMs are templates that are used for running customer workshops so we create and destroy them quite often. In OVM I can clone 10 x 100GB VM's in about 1 minute, the cloning process just creates a "delta" VM rather than copying the entire 100GB. Those VM's can then be run and the on-disk size of the delta VM grows as it runs and deviates from the master. The same goes for templates, creating a 100GB VM from a template takes only a few seconds. Creating a template from a VM only takes a few seconds. My problem is that I cant seem to do any of this using Ovirt. it appears that there is no way to tell the cloning process " I want 10" like I can in OVM - am I missing something here? In my tests I find that even if a "snapshot" is made, the entire VM is copied rather than creating a delta. Creating a VM from a template is no different in that it copies the entire VM. So... Is it possible for Ovirt to create multiple clones on request ? Can Ovirt do "delta" copies rather than copy the entire VM ? If Ovirt can do these things, how do I set it up to to do that ? Any help appreciated. thanks Tim --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus
On Tue, Sep 10, 2019 at 2:18 AM Tim Tuck <timt@skybase.net> wrote:
Hi all,
I'm new to Ovirt coming from a OVM ( aka Xen ) environment and I'm trying to work out how to do similar things.
In my OVM environment I have VMs that are 100GB in size. These VMs are templates that are used for running customer workshops so we create and destroy them quite often.
In OVM I can clone 10 x 100GB VM's in about 1 minute, the cloning process just creates a "delta" VM rather than copying the entire 100GB. Those VM's can then be run and the on-disk size of the delta VM grows as it runs and deviates from the master.
The same goes for templates, creating a 100GB VM from a template takes only a few seconds. Creating a template from a VM only takes a few seconds.
My problem is that I cant seem to do any of this using Ovirt.
it appears that there is no way to tell the cloning process " I want 10" like I can in OVM - am I missing something here?
That's definitely not my expertise, but I think most people in your position use "VM pools". Did you look into that?
In my tests I find that even if a "snapshot" is made, the entire VM is copied rather than creating a delta.
Creating a VM from a template is no different in that it copies the entire VM.
Are you sure? Does this include the VM's disk(s)? IIRC from the few times I tried that, the clone VM uses the same disk, perhaps using a snapshot of it or something like that - as I said, that's not my expertise. This might depend, though, on storage type, options, etc.
So...
Is it possible for Ovirt to create multiple clones on request ?
Can Ovirt do "delta" copies rather than copy the entire VM ?
If Ovirt can do these things, how do I set it up to to do that ?
Any help appreciated.
thanks
Tim
--- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus _______________________________________________ Users mailing list -- users@ovirt.org To unsubscribe send an email to users-leave@ovirt.org Privacy Statement: https://www.ovirt.org/site/privacy-policy/ oVirt Code of Conduct: https://www.ovirt.org/community/about/community-guidelines/ List Archives: https://lists.ovirt.org/archives/list/users@ovirt.org/message/C23QFIU6A65SKH...
-- Didi
participants (2)
-
Tim Tuck -
Yedidyah Bar David