Let us know what RAID card you end up choosing, it is payday today so I have ordered one of the 8bay U-NAS cases to start a similar project though Im undecided over whether to go for a MS solution or FreeNAS at the moment.
My problem is that I have 5 existing drives between 2TB and 4TB in size that I intend to repurpose for this so Im going to have to use some sort of drive pooling or JBOD solution
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Im sure I saw some post on Anandtech looking at the new WD drive for NAS and if I remember rightly it seems that the red series aren't meant to be used for NAS units over 6 bays?
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found it - quote
One of the most interesting launches from Western Digital last year was the WD Red line of hard drives from the client storage division. It was intended for low to mid-range NAS units (and WD wanted to make sure that it wasn't used for units with more than 5 bays). Today, the Datacenter Storage Business Unit is launching the WD Se line intended for high end NAS units and, more importantly, datacenters looking for scalable storage (i.e, reliable storage which doesn't cost an arm and a leg for scenarios where capacity, rather than performance, is of primary importance).
http://www.anandtech.com/show/6986/...s-wd-se-for-datacenters-and-highend-nas-units