The rms_decision.gif illustration shows a decision tree to help you choose the correct role transition to use. The first question asks: " Do you need to perform hardware or software maintenance on the system that currently hosts the primary database?"

If you answer Yes, then the decision tree indicates that you must "Switch over to the best available standby database."  If you answer No, then the decision tree asks you the following question: "Can you bring the primary database back online in a timely manner?"  If you answer Yes, then the decision tree indicates that you must "Resolve the problem to bring the database back online." If you answer No, then the decision tree ends with the suggestion that you should "Fail over to the best available standby database."