Description of problem:

After installing virt-manager and libvirt, and then starting virt-manager for the first time I see a dialog with this message:

Unable to connect to libvirt.

Verify that the 'libvirtd' daemon is running.

Libvirt URI is: qemu:///system

Traceback (most recent call last):
  File "/usr/share/virt-manager/virtManager/connection.py", line 1185, in _open_thread
    self.vmm = self._try_open()
  File "/usr/share/virt-manager/virtManager/connection.py", line 1167, in _try_open
    flags)
  File "/usr/lib64/python2.7/site-packages/libvirt.py", line 102, in openAuth
    if ret is None:raise libvirtError('virConnectOpenAuth() failed')
libvirtError: Failed to connect socket to '/var/run/libvirt/libvirt-sock': No such file or directory

Version-Release number of selected component (if applicable):

Name        : virt-manager
Arch        : noarch
Version     : 0.9.1
Release     : 2.fc17


How reproducible:

Every time


Steps to Reproduce:
1. Install virt-manager and libvirt
2. Double click on "localhost (QEMU)"
  
Actual results:

See the technical message.

Expected results:

virt-manager should start libvirtd if it's not yet started, whether by dbus or via systemd.