Need to perform and check disaster recovery in Bigfix envirnoment. Suggestions welcome

Hello All, With current running environment where we have a root server followed by 2 DSA and 4 top level relays, we have integration of other tools embedded in Bigfix. I need to ensure that in case if anything goes wrong at root server ( may a DB issue, Fill DB chokes up) it should automatically route to primary DSA without user and environment impact. Please advise how can we perform this. Also we need to try this by putting the root server down and to check if users, custom content and operators are directly load up their tasks from Primary DSA. Please advise how this can be done and steps involved.