Description of problem: After a Live Storage Migration of the Data disk, the OS disk is also changing to "Thin Provision". Under snapshot tab, both OS and DATA disks are marked as "preallocated" under the disks tab. This indicates that live storage migration of one disk is migration all the disks and creating the snapshot(auto generated snapshot during live storage migration). Version-Release number of selected component (if applicable): rhevm 3.3.4 How reproducible: 100% Steps to Reproduce: 1. Select a VM having multiple disks in preallocated mode. 2. Migrate a data disk from one storage domain to another. 3. It will change to 'Thin Provision' but simultaneously its migrating other disks and changing them to thin provision and making them a part of the 'auto generated snapshot during live storage migration'. Actual results: Live Storage Migration changing all the preallocated disks to Thin Provision disk. Expected results: It should not change all the disks allocation type and should not include them as a part of the snapshot created during live storage migration.
This behavior due to the limitation of being able to only snapshot an entire VM. This limitation was removed in 3.4.0 (see bug 1032679). Once this limitation was lifted, live storage migration could have been modified to only take a snapshot of the migrated disk(s). This too was done in 3.4.0, as described in bug 1056922. Closing this one as a duplicate. (Note that bug 1056922 was reported against oVirt, but I can confirm that it has been in RHEV 3.4.0 too) *** This bug has been marked as a duplicate of bug 1056922 ***