quick RAID question

i was just wondering if you could have a RAID as follows:

2 drives in RAID 0 and one drive in RAID 1 with the RAID 0 as its clone

(2x250gigs in raid 0 and one 500gig in raid one with the 2 250gigs)

also, for RAID 0 do the drives need to be the same size?

 

Not exactly... What you are talking about would be Raid 0+1. You would need 4x250Gb (Or any amount) drives. Nearly all RAID controllers can do 0, 1, and 0+1.

RAID 5 is another option. You can do RAID 5 with 3 or more hard drives, but controllers that offer RAID 5 support are a little bit more expensive.

Wikipedia has a much more in depth explanation:
http://en.wikipedia.org/wiki/Redundant_array_of_independent_disks

You know, you could try Googling for information before just coming here to ask the question.