4-Drive RAID 5 configuration?

[TJN23]

Question about RAID 5: can a server have 4 physical drives, 3 of which are running RAID 5 and one of which is running another RAID configuration?

Another way to pose the question: in a 4 drive setup, do all of the drives have to be running the same RAID array?

 

[Rilex]

Well, you can have 3 drives in RAID-5 and one as a stand alone (it would not be a part of any RAID array). Or you could have 4 drives in RAID-5 and 2 drives in RAID-1....etc. The only limitation here is A) how many drives can you fit in your box, and B) will your controller let you do it.