Re: [libvirt] [PATCH] libvirtd: systemd: add special target for system shutdown

It is already discussed in "[RFC] daemon: remove hardcode dep on libvirt-guests" [1]. Mgmt can use means to save/restore domains on system shutdown/boot other then libvirt-guests.service. Thus we need to specify appropriate ordering dependency between libvirtd, domains and save/restore service. This patch takes approach suggested in RFC and introduces a systemd target, so that ordering can be built next way: libvirtd -> domain -> virt-guest-shutdown.target -> save-restore.service. This way domains are decoupled from specific shutdown service via intermediate target.