I noticed Cloudmin shuts down a guest by either sending the shutdown command through ssh or webmin, where it has access to the guest; where it doesn't have access it just "cuts power". Am I wrong?
Would it be possible to send the acpi shutdown through qemu monitor instead? (i think it's called "system_powerdown"). That would be great, especially as both linux distros and windows (at least 2008) respect this; so cloudmin doesn't have to rely on ssh access which might not even be available at all.
Willing to test if it helps.