Kevin Wolf píše v Po 14. 04. 2014 v 12:52 +0200: > Am 14.04.2014 um 12:33 hat Pavel Lisý geschrieben: > > Hello > > > > I've made virtual guest on Fedora 20 (x86_64) within qcow2 image file > > but after migration to CentOS 6.5 I've got this error: > > > > qemu-kvm: -drive > > file=/var/lib/libvirt/images/questfile.qcow2,if=none,id=drive-virtio-disk0,format=qcow2: > > 'drive-virtio-disk0' uses a qcow2 feature which is not supported by this > > qemu version: QCOW version 3 > > > > similar error I've got for qemu-img: > > # qemu-img info /var/lib/libvirt/images/questfile.qcow2 > > 'image' uses a qcow2 feature which is not supported by this qemu version: > > QCOW version 3 > > > > On F20 it returns: > > # qemu-img info /var/lib/libvirt/images/questfile.qcow2 > > image: /var/lib/libvirt/images/rhel6.qcow2 > > file format: qcow2 > > virtual size: 32G (34359738368 bytes) > > disk size: 4.7G > > cluster_size: 65536 > > > > > > Have I missed something? > > > > Is it qcow2 on Fedora different from CentOS6? Is there any possibility > > (on Fedora 20) to convert it to backward compatible format? > > qemu versions starting with 1.1 can use new qcow2 features which require > an incompatible on-disk format. Between version 1.1 and 1.6, they needed > to be specified explicitly during image creation, like this: > > qemu-img create -f qcow2 -o compat=1.1 test.qcow2 8G > > Starting with qemu 1.7, compat=1.1 became the default, so that newly > created images can't be read by older qemu versions by default. If you > need to read them in older version, you now need to be explicit about > using the old format: > > qemu-img create -f qcow2 -o compat=0.10 test.qcow2 8G > > With the same release, qemu 1.7, a new qemu-img subcommand was > introduced that allows converting between both versions, so you can > downgrade your existing v3 image to the format known by RHEL 6 like > this: > > qemu-img amend -f qcow2 -o compat=0.10 test.qcow2 > > However, it looked to me as if F20 still had qemu 1.6, so you shouldn't > be seeing any of this, and your qemu-img may not have the 'amend' > subcommand. Maybe one of the package maintainers can comment on any > patches that F20 has on top of 1.6? you are right, there is no such option
in meantime I've found example on ubuntu forum and then in man page qemu-img convert -p -f qcow2 -O qcow2 -o compat=0.10 \ fedora20-guest.qcow2 centos6-guest.qcow2 I think for CentOS/RHEL6 compat=0.10 is necessary, there are qemu-kvm-0.12 qemu-img-0.12 only It works now, thanks Pavel -- Pavel Lisý <pa...@element.cx> _______________________________________________ virt mailing list virt@lists.fedoraproject.org https://admin.fedoraproject.org/mailman/listinfo/virt
