By accident I ran a second instance of libvirtd. This second instance did
not terminate the first instance nor did it detect there was already a
running instance. By killing the second instance the first did not work
anymore.
Next to this, why does libvirtd terminate its iSCSI connections upon stop?
I saw it cannot gracefully 'reuse' existing sessions, but it is absurd
that restarting libvirtd would kill all running VMs on a host using iSCSI,
or not able to get a storage pool up because it is already logged in to
it.
Stefan