Re: [libvirt] [PATCH 0/2] Alter refresh algorithm for volWipe

On 08/25/2017 05:44 AM, Martin Kletzander wrote: > On Thu, Aug 24, 2017 at 06:28:27PM -0400, John Ferlan wrote: >> Alter wipeVol to do same refresh operation as pool refresh would do. >> > > I think we should rather keep the format as it is. Did I miss something > here or isn't the source of the problem just the fact that we wipe the > volume without keeping the format? > Once you "wipe" the file/image the format that was there (such as qcow2 as noted in the bz from patch2) is no longer there. Consider the following sequence: virsh vol-create-as default bz 10M --format qcow2 virsh vol-dumpxml bz default | grep format <format type='qcow2'/> qemu-img info /home/vm-images/bz image: /home/vm-images/bz file format: qcow2 virtual size: 10M (10485760 bytes) disk size: 196K cluster_size: 65536 Format specific information: compat: 0.10 refcount bits: 16 virsh vol-wipe bz default qemu-img info /home/vm-images/bz image: /home/vm-images/bz file format: raw virtual size: 196K (200704 bytes) disk size: 196K virsh vol-dumpxml bz default | grep format <format type='qcow2'/> (without the patch in 2/2 of course) BTW: I did consider just changing the format to RAW regardless, but figured that was just too simple and may not be the right answer for every case.