If I create a preallocated disk for a VM, I see th= e =3D disk image file listing as the size I requested (100G):

cd /rhev/data-center/mnt/storage_host1:_vol_pa1__nas= =3D __01b__oVirt__prod__01/53560d43-874a-49c5-9c5a-8b90487c79f8/images/d97f7706= =3D -3662-40bf-9358-80e0dc51bff4

root(a)ovirt_host> ls -l

total 105064644

-rw-rw---- 1 vdsm kvm 107374182400 Aug 5 10:57= =3D 75c14559-e18f-4cc8-a3fe-bc0de507720b

-rw-rw---- 1 vdsm kvm = =3D 1048576 Aug 5 10:57 75c14559-e18f-4cc8-a3fe-bc0de507720b.lease

-rw-r--r-- 1 vdsm kvm &= =3D nbsp; 313 Aug 5 10:57 75c14559-e18f-4cc8-a3fe-bc0de= =3D 507720b.meta

and the corresponding space used on disk matches

root@ ovirt_host > du -sh *

101G 75c14559-e18f-4cc8-a3fe-bc0de= =3D 507720b

1.1M 75c14559-e18f-4cc8-a3fe-bc0de= =3D 507720b.lease

4.0K 75c14559-e18f-4cc8-a3fe-bc0de= =3D 507720b.meta

If I then migrate that storage (while the VM is sh= ut=3D down) to a new storage domain, the size on disk does not match the allocate= =3D d size. In this case there is nothing in the disk yet so it shows as 0.

cd /rhev/data-center/mnt/storage_host2:_vol_pa1__ovi= =3D rt__uatprod/1f2c2b48-1e77-4c98-a6da-5dc09b78cead/images/d97f7706-3662-40bf-= =3D 9358-80e0dc51bff4

root@ ovirt_host> ls -l

total 1032

-rw-rw---- 1 vdsm kvm 107374182400 Aug 5 11:06= =3D 75c14559-e18f-4cc8-a3fe-bc0de507720b

-rw-rw---- 1 vdsm kvm = =3D 1048576 Aug 5 11:06 75c14559-e18f-4cc8-a3fe-bc0de507720b.lease

-rw-r--r-- 1 vdsm kvm &= =3D nbsp; 313 Aug 5 11:06 75c14559-e18f-4cc8-a3fe-bc0de= =3D 507720b.meta

root@ ovirt_host > du -sh *

0 75c14559-e18f-= =3D 4cc8-a3fe-bc0de507720b

1.1M 75c14559-e18f-4cc8-a3fe-bc0de= =3D 507720b.lease

4.0K 75c14559-e18f-4cc8-a3fe-bc0de= =3D 507720b.meta

oVirt still lists the disk as preallocated in the = GU=3D I but it is in fact thin provisioned.

I see the same issue if I clone a preallocated VM.= T=3D he size on disk ends up being the equivalent of a thin-provisioned disk. I = =3D also had the issue when importing VM’s from an export domain when I h= =3D ad selected preallocated in the import dialog box.

Is this a known issue? Should preallocated not mea= n =3D preallocated on physical disk?

Ovirt Engine is running 3.6.4.1-1.el6

The ovirt nodes are running:

OS Version: &nb= sp=3D ; &= =3D nbsp; RHEL - 7 - 2.1511.el7.centos.2.10

Kernel Version: &nbs= p;=3D 3.10.0 - 327.4.5.el7= =3D .x86_64

KVM Version: &= nb=3D sp; 2.3.0= =3D - 31.el7_2.7.1

LIBVIRT Version: &nbs= p;=3D libvirt-1.2.17-13.el7_2.2<= =3D o:p>

VDSM Version: = &n=3D bsp; vdsm-4.17.23.2-0.el7.c= =3D entos

SPICE Version: = ;&=3D nbsp; 0.12.4 - 15.el7= =3D

GlusterFS Version: &n= bs=3D p; [N/A]

CEPH Version: = &n=3D bsp; librbd1-0.= =3D 80.7-3.el7

Many thanks,

Simon