On Fedora 20, libvirt-python 1.2.9-2 is not available, missing a fix for this bug: $ yum info --enablerepo=fedora-virt-preview libvirt-python Installed Packages Name : libvirt-python Arch : x86_64 Version : 1.1.3.9 Release : 1.fc20 Size : 1.0 M Repo : installed From repo : updates Available Packages Name : libvirt-python Arch : x86_64 Version : 1.2.9 Release : 1.fc20 Size : 225 k Repo : fedora-virt-preview/20/x86_64 Vdsm requires libvirt-1.2.9, available only via virt-preview repo, but without libvirt-python-1.2.9-2, we cannot use the new virDomainBlockCopy api.
I pushed the updated libvirt-python to f20 virt-preview now