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I want to purchase 2 x 2TB drives, and install FreeNas on my Dell Powervault 745N.

People on the internets seem to be having trouble with the MD3000 firmware, and I want to make sure I can solve any issues before buying the drives.

Before I invest, I have 3 questions :

  1. Is there a partition size limit determined by the RAID controller? That is, could I have a striped 4TB partition?

  2. The spec sheets make me wonder if the RAID controller needs all 4 drives in order to work. Is there any reason this will have to run in RAID5?

  3. If I buy 4 matching drives, would the controller support a RAID6 configuration?

I'm basically new to all this RAID stuff - sorry for any noob questions.

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up vote 1 down vote accepted

1 - The 745N uses a CERC controller if I remember correctly, and its maximum array size is 2TB per array.

What this means is that if you have total disk space (after parity overheads) > 2TB then you'll have to create multiple arrays to maximise your capacity.

2 - Generally no, devices will work with any disks that match your chosen RAID level. RAID 5 requires a minimum of 3 disks, RAID6 4 disks, RAID1 2 disks.

3 - I don't believe the 745N supports RAID6

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