There seems to be many, the clone and the snapshot features in my VMWare vSphere web client is grayed out for somereason, (I have sent a mail enquiring about this to my SP). Rsync and Cron, seems to be commonly used, but there are many nuances involved there. Then there are several 3rd party programs, I'm opting to give Systemback a try (looks easy enough to install and use.
Clone probably is for getting another host identical to the original. Not meant for backups. Snapshot sounds like suitable tool to use before major changes to the virtual host.
