Ok I've a HP mircoserver that I'm building up. It's got 4 bays for be used for data that I'm considering setup up woth softwere raid (mdadm) I've 2 x 2TB 2 x 2.5 TB and 2 x 1TB, I'm leaning towards usig the 4 2.x TB is a raid 5 array to get 6TB. Now the data is on the 2.5TB disks currently. So the plan so far. Building the array as a degraded raid 5 with the 2 x 2TB disks that are emply. Copy the data from one of the 2.5TB disks on to array. Add now empty 2.5TB disk to the Array and wait for it to rebuild. Copy contents of remaining 2.5TB disk 2 array. Add now empty 2.5TB disk to the Array and wait for it to rebuild. So questions... Is the above a stupid idea? Do I need to get involved in gptids? on disks this size? What format should I create the file system as? Should I get lvm involved somewhere? Any pointers would be kindly appreciated. Jeff