To enable libvirtd please add libvirtd_enable="YES" to
/etc/rc.conf.

NOTE ON CONFIGURATION:

The libvirt port does not come with networking configuration enabled.
The 'default' network definition is available at:

  %%EXAMPLESDIR%%/networks/default.xml

To enable this network please do the following:

  cp %%EXAMPLESDIR%%/networks/default.xml %%ETCDIR%%/qemu/networks

To configure this network for autostart, execute the following:

  ln -s ../default.xml %%ETCDIR%%/qemu/networks/autostart/default.xml

If you have libvirtd already running you'll need to restart it for changes
to take effect.