I'm running an two node RAC database with ASM having two DGs one for data and one for redo. I have only one copy of redo and I have the need to have another copy of redo logs. 1. How to go ahead with adding mirror copies of redo? 2. Will it demand downtime? 3. Can I add the copies which I'm going to create in the data DG? 4. I also need to create a copy for the control file. How can I do that as well?