I'm planning to build a new server and am currently deciding what drives to purchase and how to organize them. I would like to use multiple drive sizes to offset the tendency of drives to fail from the same manufacturing batches. As I am new to RAID, I'm not quite sure about all the ways to go about doing this. My latest idea was to have multiple arrays mirrored, with each array composed of different sized drives in a single pool, but that creates a problem for expansion if I cannot find the same sized drives in the future. What I am looking for is some sort of RAID setup in which differently sized drives can be added and removed. Something like JBOD, but with redundancy. Does anyone have any suggestions for this? Thank you.