Hi Max,
Unfortunately there is no built in functionality in Proview that supports this. You will have to do some tricks yourself to make this work. You can for example connect to Proview-systems to the same Profibus-net where one is just a backup and initiates its Profibus-master if the other goes down. You will yourself have to make sure that you mirror the state of the first machine to the other. It will be a lot of work to make it work...
/robert