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* differencing disks support
@ 2011-06-08 20:09 Iordan Iordanov
  2011-06-08 20:33 ` Dan VerWeire
  2011-06-09  6:24 ` Markus Armbruster
  0 siblings, 2 replies; 3+ messages in thread
From: Iordan Iordanov @ 2011-06-08 20:09 UTC (permalink / raw)
  To: kvm

Does KVM support or plan to support differencing disks (where there is a 
read-only source disk, and each person running a virtual machine can 
save block-level changes that their virtual machine is making to the 
disk in a separate "differencing" image)?

If so, can somebody suggest how I may make use of this feature (i.e. 
building the newest version from source, and any other requirements).

Thanks!
Iordan

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: differencing disks support
  2011-06-08 20:09 differencing disks support Iordan Iordanov
@ 2011-06-08 20:33 ` Dan VerWeire
  2011-06-09  6:24 ` Markus Armbruster
  1 sibling, 0 replies; 3+ messages in thread
From: Dan VerWeire @ 2011-06-08 20:33 UTC (permalink / raw)
  To: Iordan Iordanov; +Cc: kvm

On Wed, Jun 8, 2011 at 4:09 PM, Iordan Iordanov <iordan@cdf.toronto.edu> wrote:
> Does KVM support or plan to support differencing disks (where there is a
> read-only source disk, and each person running a virtual machine can save
> block-level changes that their virtual machine is making to the disk in a
> separate "differencing" image)?
>
> If so, can somebody suggest how I may make use of this feature (i.e.
> building the newest version from source, and any other requirements).
>
> Thanks!
> Iordan


I believe you could accomplish this with LVM2 snapshots. You would
create an LVM volume with the base install or set of data or whatever.
Then create snapshots of the original volume. Have your guests use the
snapshot volumes.

This page mentions doing it with Xen in the last paragraph:
http://tldp.org/HOWTO/LVM-HOWTO/snapshotintro.html

If you need support in qemu specifically for some reason, that's out
of my realm. Hope this helps though.

Dan VerWeire

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: differencing disks support
  2011-06-08 20:09 differencing disks support Iordan Iordanov
  2011-06-08 20:33 ` Dan VerWeire
@ 2011-06-09  6:24 ` Markus Armbruster
  1 sibling, 0 replies; 3+ messages in thread
From: Markus Armbruster @ 2011-06-09  6:24 UTC (permalink / raw)
  To: Iordan Iordanov; +Cc: kvm

Iordan Iordanov <iordan@cdf.toronto.edu> writes:

> Does KVM support or plan to support differencing disks (where there is
> a read-only source disk, and each person running a virtual machine can
> save block-level changes that their virtual machine is making to the
> disk in a separate "differencing" image)?
>
> If so, can somebody suggest how I may make use of this feature
> (i.e. building the newest version from source, and any other
> requirements).

Check out image format qcow2.

LVM snapshots were already mentioned.

^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2011-06-09  6:25 UTC | newest]

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2011-06-09  6:24 ` Markus Armbruster

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