Thanks all for the promptness of your responses and the details you have provided it is greatly appreciated. Since this is a home media server performance isn't imperative and mirroring and RAID 10/0+1 are too expensive so I am going to use my three existing drives of different manufactures as they are all reasonably new (each was purchased at different times this year) and throw in two more giving four drives for data and one for parity. That will suffice in terms of storage size (4TBs) and a ratio of four data drives to one parity is as far as I feel comfortable in terms of hardware redundancy. I have read a few articles about mdadm and I have devised the following strategy in my head and am looking for some confirmation of its theoretical success: Two of my existing three drives are full of data. I will purchase two more drives to go with my existing blank drive and set them up as a RAID 5 > copy my existing data on to the new file system one drive at a time and after each drive has been copied I will add said drive and use mdadm --grow to then incorporate that drive into the RAID before adding the next drive. Can anyone point out a flaw in this plan or more preferred method for doing this, or have I, dare I say it, got it right? Also I was initially going to get a PCI-E SATA card to connect up all these drives and use mdadm to make a software RAID, for this particular setup is that ill advised or do people think this will suffice (simple because my budget is low and hardware RAID controller cards are more expansive, in my experience but if you know of a good bargain I'm all ears!). Just quickly, this brings me back to the issue of a hot swappable drive. Up time isn't critical as its a home server so I don't believe a hotspare is needed, in the event of a drive failure I can shutdown the server and fire up single user mode and have the RAID file system dismount and then replace the failed drive and rebuild the array, is this correct? Thank you for you time guys it has been very much appreciated. Regards, James ;) Joan Crawford - "I, Joan Crawford, I believe in the dollar. Everything I earn, I spend." - http://www.brainyquote.com/quotes/authors/j/joan_crawford.html