On Tue, May 14, 2013 at 12:16:32PM +0200, Wido den Hollander wrote: > Hi, > Hi Wido, > While working on the CloudStack code for 4.2 I'm running into some > problems with QCOW2 and RBD format 2. > > A quick cap of the problem: > > CloudStack stores all the templates on "Secondary Storage" as QCOW2 files. > > When a VM is deployed, this image will be copied (once) from > Secondary Storage to Primary Storage, this is done by qemu-img which > does the conversion. > > When the image is on Primary Storage it will be copied to the > destination volume and the Instance/VM is started. > > In that last step I want to use layering, but the problem is that my > image is RBD format 1 due to the qemu-img copy. > > I can skip the qemu-img copy, but I have to find a way to go from > QCOW2 to RBD format 2 in preferably one step. There is a issue about > this in the tracker [0], but that won't be finished on time. > > Another idea would be to do QCOW2 -> RAW -> RBD format 2, but that > extra step will take a lot of time. It would also require some > temporary storage on the hypervisor. > > I also thought of creating the RBD image prior to converting to it, > but that fails, since qemu-img won't let you convert to a already > existing image. > > Any brights ideas? Maybe even doing the QCOW2 -> RAW format in > memory? In Java? > I'm no expert, but would it be possible to change qemu-img to support writing RAW to standard out ? So you can run qemu-img convert and pipe that drectly to the rbd import command ? rbd import already supports standard in I believe. Then you don't need any temporary storage. Maybe something more efficient than RAW is possible as well ? > The goal is to go from QCOW2 to RBD format 2 in one step. > > [0]: http://tracker.ceph.com/issues/4897 > > -- > Wido den Hollander > 42on B.V. > > Phone: +31 (0)20 700 9902 > Skype: contact42on > -- > To unsubscribe from this list: send the line "unsubscribe ceph-devel" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
