It seems the main issue was that libvirt-daemon-system was not installed after the update. Found that by searching for /etc/libvirt/qemu.conf
In addition I had to put the default network to active: rd@h370:~$ apt-file search qemu.conf libvirt-daemon-system: /etc/libvirt/qemu.conf rd@h370:~$ root@h370:~# apt-get install libvirt-daemon-system [...] root@h370:~# addgroup rd libvirt Füge Benutzer »rd« der Gruppe »libvirt« hinzu ... Benutzer rd wird zur Gruppe libvirt hinzugefügt. Fertig. root@h370:~# virsh net-list --all Name Status Automatischer Start Bleibend ----------------------------------------------------- default Inaktiv nein ja root@h370:~# virsh net-start default Netzwerk default gestartet root@h370:~# virsh net-list --all Name Status Automatischer Start Bleibend ---------------------------------------------------- default Aktiv nein ja root@h370:~# https://askubuntu.com/questions/1036297/cant-start-kvm-guest-network-default-is-not-active I think the core of the issue is rather why libvirt-daemon-system was installed after the upgrade, the documentation seems to be ok for me. Even from having not found /usr/share/doc/libvirt-daemon-system/README.Debian.gz I could have concluded that libvirt-daemon-system is missing, but I concluded wrongly that the package was renamed. Thanks Rainer -- Rainer Dorsch http://bokomoko.de/
