[libvirt-users] Cannot create PID file

[Michal Prívozník]

On 4/4/19 6:22 PM, Nicolás Iglesias wrote:
> Hi Fellow users
> 
> I've just compiled latest libvirt and qemu, both from their respective official repositories.
> Libvirtd starts perfect, but when I try to start a domain using the virsh console, I get the following:
> 
> virsh # start --domain win8.1
> error: Failed to start domain win8.1
> error: internal error: Failed to start QEMU binary /usr/bin/qemu-system-x86_64 for probing: qemu-system-x86_64: cannot create PID file: Cannot open pid file: Permission denied
> 
> I'm not sure where to look at. Any hint would be much appreciated.

Hi,

when probing for capabilities libvirt starts qemu with:

  -pidfile $libDir/qmp-XXXXX/qmp.pid

where $libDir points to /var/lib/libvirt/qemu for system wide daemon and
$XDG_CACHE_HOME/.cache/qemu/lib/ for session daemon. qemu process is run
under user:group configured from corresponding qemu.conf
(/etc/libvirt/qemu.conf for system daemon). The defaults are distro
specific.

Hope this gives you some hint. Although, libvirt should relabel its
internal paths on daemon startup, so this smells like a bug.

Michal