Description of problem: If a drive was enlarged after creation of a snapshot then the volume associated with the snapshot will be smaller than the currently active volume. If the snapshot volume is also on preallocated block storage then engine needs to manually enlarge the snapshot volume prior to starting a live merge. Today, engine issues the extendVolumeSize call to SPM but it does not notify the host running the VM (HSM host) that the volume has been resized. This means that when a VM is running on a non-SPM host the resize won't be picked up by qemu and the merge will fail. Version-Release number of selected component (if applicable): ovirt-engine-4.0.0-0.0.master.20151020161541.git37557f3.el7.centos.noarch How reproducible: Always Steps to Reproduce: 1. Start a VM on a non-SPM host with a preallocated block disk 2. Create a snapshot involving the disk 3. Enlarge the disk by 1GB 4. Delete the snapshot Actual results: The merge fails with an error like the following on the HSM host: libvirtError: internal error: unable to execute QEMU command 'block-commit': Top image /rhev/data-center/108151fa-1c40-4ee3-bae0-d91d0e56f44d/2276ca67-cdff-4bde-b437-446fc2e92a46/images/65ade35f-deed-4e0d-8a73-7c98c80fb661/b97c3c80-f781-4b51-bb79-5929fd9f3cf8 is larger than base image /rhev/data-center/108151fa-1c40-4ee3-bae0-d91d0e56f44d/2276ca67-cdff-4bde-b437-446fc2e92a46/images/65ade35f-deed-4e0d-8a73-7c98c80fb661/71bc1e19-e392-4121-9c2f-896d7402db22, and resize of base image failed: Invalid argument Expected results: The snapshot should be removed successfully. Additional info:
Created attachment 1085521 [details] engine.log
Created attachment 1085522 [details] vdsm log from SPM host
Created attachment 1085524 [details] vdsm log from HSM host
I believe the proper way to fix this is for engine to issue a diskSizeExtend to the HSM host as discussed in the Feature Page for online disk resize: http://www.ovirt.org/Features/Online_Virtual_Drive_Resize#Detailed_Description
In oVirt testing is done on single release by default. Therefore I'm removing the 4.0 flag. If you think this bug must be tested in 4.0 as well, please re-add the flag. Please note we might not have testing resources to handle the 4.0 clone.
Patch was merged to the upstream ovirt-3.5 branch, but we currently aren't planning to have a 3.5.7 build. Closing.