Solve problem for Ubuntu 15.10
$ sudo vi /etc/systemd/system/multi-user.target.wants/libvirt-bin.service
Change line ExecStart=/usr/sbin/libvirtd $LIBVIRTD_ARGS to ExecStart=/usr/sbin/libvirtd -l $LIBVIRTD_ARGS add -l option
Then: $ sudo systemctl daemon-reload $ sudo service libvirt-bin restart
Solve problem for Ubuntu 15.10
$ sudo vi /etc/systemd/ system/ multi-user. target. wants/libvirt- bin.service
Change line /usr/sbin/ libvirtd $LIBVIRTD_ARGS /usr/sbin/ libvirtd -l $LIBVIRTD_ARGS
ExecStart=
to
ExecStart=
add -l option
Then:
$ sudo systemctl daemon-reload
$ sudo service libvirt-bin restart