Ошибка не появляется, если я запускаю gksudo virt-manager.

  • libvirt-bin is installed.
  • I don't know how to check for the daemon.
  • I am a member of libvirtd.

Выход ps ax | grep libvirt:

9225 ? Sl 0:04 /usr/sbin/libvirtd -d
9302 ? S 0:00 /usr/sbin/dnsmasq -u libvirt-dnsmasq --strict-order --bind-interfaces --pid-file=/var/run/libvirt/network/default.pid --conf-file= --except-interface lo --listen-address 192.168.122.1 --dhcp-range 192.168.122.2,192.168.122.254 --dhcp-leasefile=/var/lib/libvirt/dnsmasq/default.leases --dhcp-lease-max=253 --dhcp-no-override`

Выход ls -l /var/run/libvirt/libvirt-sock:

srwxrwx--- 1 root libvirtd 0 Set 13 15:04 /var/run/libvirt/libvirt-sock

Выход getent group libvirtd:

libvirtd:x:130:OTHERUSER,MYUSER

Подробное сообщение об ошибке

Unable to connect to libvirt.   
Failed to connect socket to '/var/run/libvirt/libvirt-sock': Permission denied

Verify that:
 - The 'libvirt-bin' package is installed
 - The 'libvirtd' daemon has been started
 - You are member of the 'libvirtd' group

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/lib/python2.7/dist-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': Permission denied

Решение:

1. Авторизованный пользователь должен быть добавлен в libvirtгруппу пользователей

sudo usermod -a -G libvirt $USER

2. Выполнить команды:

sudo apt install libvirt-daemon-system

sudo systemctl start libvirtd

Перезапустить систему.

3. 

loginctl terminate-user <user> где пользователь входит в GNOME.
sudo systemctl restart gdm