Description of problem: Newer QEMU versions support a new format of QCow2[1], which is not backwards compatible, and currently not supported in oVirt [2]. Since this new format offers many improvements (most notably zero clusters), we'd want to utilize it. This would require a new storage format in order to differentiate domains which allow this format and domains that do not. Having a new domain format will also serve to streamline VDSM operations without an SPM, and prevent ugly hacks to determine whether we have one running or not. [1] http://qemu.weilnetz.de/qemu-doc.html#disk_005fimages_005fformats [2] See bug 1139707.
Open issue - what to do with pre-existing images when upgrading V3 to V4? Offhand, there are several issues: 1. Nothing. Leave them as is, and just create new images with compat=1.1 2. Option #1 + a manual tool to "upgrade" images 3. Option #1 + engine support to "upgrade" images (disk -> right click -> upgrade) 4. Upgrade all of them synchronously when upgrading the domain.
*** Bug 827528 has been marked as a duplicate of this bug. ***
*** Bug 827529 has been marked as a duplicate of this bug. ***
Will be handled after removing SPM, need to see how this fits the timeline
I thought most of the work is already done by Maor?
The current status regarding this RFE is as follow: 1. Upgrading a DC to 4.1 should upgrade all data storage domains to V4. 2. All new volumes created on a 4.1 Data Center should be created with qcow version 1.1. That includes new disks, snapshots, Templates or VMs based on Templates (only the active volumes if thin provisioned) Old volumes will be configured with 0.10 compat level. 3. A user will be able to check its disk's qcow version through REST: http://localhost:8080/ovirt-engine/api/storagedomains/1234/disks/ 4. If a user will want to upgrade its disk's qcow version he can use the REST API upgrade to amend the disk's qcow compat to 1.1 I will add the relevant patches to this bug so it can be better tracked.
Should be MODIFIED?
(In reply to Yaniv Dary from comment #17) > Should be MODIFIED? yes
Hi Maor Is there a need to update any of the documentation with this new version of QCOW2?
(In reply to emma heftman from comment #20) > Hi Maor > Is there a need to update any of the documentation with this new version of > QCOW2? Yes, we should indicate that new volumes on DC 4.1 will be with qcow compat of 1.1 as described in here: http://www.ovirt.org/develop/release-management/features/storage/qcow2v3/
MOVING TO VERIFIED
Removing doc text because this bug is duplicated in the release notes.
Sync with Jira