Hi! Simple volume definition: <volume type='file'> <name>tstlog01-system</name> <capacity unit='GiB'>20</capacity> <target> <compat>1.1</compat> <format type='qcow2'/> </target> </volume> # virsh vol-create --pool libvirt-ssd0 --file vm-files/tstlog01/tstlog01-sys tem-vol.xml --validate error: Failed to create vol from vm-files/tstlog01/tstlog01-system-vol.xml error: unsupported flags (0x4) in function virStorageVolDefParseXML Omitting --validate creates volume # virsh vol-dumpxml --pool libvirt-ssd0 --vol tstlog01-system <volume type='file'> <name>tstlog01-system</name> <key>/var/lib/libvirt/images/tstlog01-system</key> <capacity unit='bytes'>21474836480</capacity> <allocation unit='bytes'>200704</allocation> <physical unit='bytes'>196928</physical> <target> <path>/var/lib/libvirt/images/tstlog01-system</path> <format type='qcow2'/> <permissions> <mode>0600</mode> <owner>0</owner> <group>0</group> <label>system_u:object_r:virt_image_t:s0</label> </permissions> <timestamps> <atime>1730277533.331347844</atime> <mtime>1730277533.329347839</mtime> <ctime>1730277533.330347841</ctime> <btime>0</btime> </timestamps> </target> </volume> # file /var/lib/libvirt/images/tstlog01-system /var/lib/libvirt/images/tstlog01-system: QEMU QCOW2 Image (v2), 21474836480 bytes # virsh vol-create-as libvirt-ssd0 tstlog01-system 20g --format qcow2 Vol tstlog01-system created # virsh vol-dumpxml --pool libvirt-ssd0 --vol tstlog01-system <volume type='file'> <name>tstlog01-system</name> <key>/var/lib/libvirt/images/tstlog01-system</key> <capacity unit='bytes'>21474836480</capacity> <allocation unit='bytes'>200704</allocation> <physical unit='bytes'>196928</physical> <target> <path>/var/lib/libvirt/images/tstlog01-system</path> <format type='qcow2'/> <permissions> <mode>0600</mode> <owner>0</owner> <group>0</group> <label>system_u:object_r:virt_image_t:s0</label> </permissions> <timestamps> <atime>1730277391.657950326</atime> <mtime>1730277391.656950323</mtime> <ctime>1730277391.657950326</ctime> <btime>0</btime> </timestamps> </target> </volume> It seems both volumes are identical - the one created without --validate and the one created with vol-create-as. Questions: 1) Why does validation fail? How to debug it? 2) Why doesn't libvirt create qcow2 v3 even when specifying compat 1.1? When creating an image using virt-manager on the same libvirt hypervisor host, v3 images are created. Alma Linux 9.4, libvirt-10.0.0-6.7.el9_4.alma.1.x86_64, qemu-kvm-8.2.0-11.el9_4.6.x86_64 With best regards, Veiko