Keeping two systems in sync

[bdbriley]

I am sure there is a way and several searches have not revealed the trick but how does one keep both systems ( Primary and backup), in sync with changes done to the Hoster setup. Like adding instabuttons sound tabs, display preferences etc. Is there a config file that gets copy over to the backup so both will look alike at the show should you have to take the primary down for some reason?

Thanks
Bob