Backup Instance?

Hello,  

This question has probably been asked before, but I couldn't find a FAQ for this NG.
Is it possible to make a backup instance of an Oracle database, and then take the (archived) log files from one instance and apply it to the other so the result will be two identical instances?

I'm sure many rules and restrictions apply in making backup instances, can somebody tell what they might be?

Thanks in advance.

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Eugene