Windows normally require far more frequent patching than Linux. There is one issue with VPS. Everytime we do maintenance we need to reboot the server and the VPS are affected. Normally for VPS I thought the best method will be to remote into the VPS first to shut them all down before rebooting the main server.
Issue is sometimes clients want security and do not give us these passwords. If we were to shut down by the main server interface and reboot, won't it harm the VPS? For those doing maintenance, what are your ways of overcoming these?
What I've done in the past with windows based virtual machine hosts, is to just firewall everything off them and only run updates periodically (before a scheduled reboot every 6 months or something)
What virtualisation technology are you using? VPS servers on vmware for eg with vmware tools installed for instance should shutdown gracefully before the server reboots (part of the vmware process stopping).
I've never really run into any issues other than lock files preventing vps's starting up, after a hard reboot of a vps host for instance.