What version of QEMU do you have installed ? Libvirt has recently become more aggressive at requiring modern QEMU versions, so its possible if your old libvirt was running against old QEMU, that might not be supported with new libvirt.
I'm using QEMU 2.8 here. That might explain why libvirt cannot find a version that is modern enough.
2.8 is plenty new enough, so that's not the issue.
Alright, so let's focus on libvirt 4.4.0. When I start the daemon, i can see some warnings related to QEMU: warning : virQEMUCapsInit:942 : Failed to get host CPU cache info warning : virQEMUCapsInit:949 : Failed to get host power management capabilities Could this be the reason, or the beginning of an explanation ? How can I dig and find what is the root cause ? -- Mathieu Tarral