[one-users] OpenNebula ceph snapshots problem.

[Stuart Longland]

On 17/04/14 01:18, Leszek Master wrote:
> 1) I'm using OpenNebula 4.4 with ceph datastore. When i try to make
> snapshot i've got error:
> 3) Is there any way to use copy-on-write in opennebula 4.4 ?

I did some experimental work on this with our OpenNebula 4.4 instance.
It relies on modern kernel's ability to map version-2 RBD images using
the kernel rbd driver, so it needs kernel >3.10 (? Not sure of exact
version; we're using 3.13).

This newer format allows copy-on-write cloning.  "Hot" snapshots work,
however I haven't managed to trigger a deferred snapshot, so that's
untested.  The driver also makes use of hypervisor-side cache using
FlashCache, allocating slices of a nominated LVM volume to boost
performance.

I've thrown my work into a git repository for now, consider this very
much pre-alpha.  If you're brave, feel free to give it a go:

git clone git://git.longlandclan.yi.org/opennebula-ceph-flashcache.git

Regards,
-- 
Stuart Longland
Systems Engineer
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