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Disclaimer: I've never used FreeNAS or any type of RAID before, so this is a first.

I've decided to build a media server in my new apartment. I'm going to be going with a total 10TB of space (6x2TB discs in a RAID 5, unless I get recommendations to use another RAID). I've also decided to go with FreeNAS on a recommendation of a friend. Here are some of my issues regarding this setup:

  • Seeing as buying 6 2TB drives is quite a bit of money, I was wondering how hard it would be to say start with 3 discs, wait until they are full, then add another disc to the array. Is this even possible with RAID5?

  • My media is currently on 3 1TB drives (non-RAIDed). How straightforward is it to use FreeNAS to transfer files over? I assume I would have to set up my RAID first, then transfer the old files into it one hard drive at a time, right?

Also, how would the above differ if I was using RAIDZ (I'm not quite sure how easy it is to set up)

share|improve this question
Adding disks to a RAID5 array is not a simple operation, it requires moving a lot of data around. Linux's mdraid supports this (the raid driver moves the data while the system is live), I don't know about FreeBSD. – Gilles Apr 21 '12 at 23:31
If I decide to go the Linux way and use mdraid, does it require having a second set of discs? Or can it work with only the existing array and the new disc coming in? – n0pe Apr 21 '12 at 23:39
Linux can add a disk at a time to a RAID5 or RAID6 array. – Gilles Apr 21 '12 at 23:49
The question about RAIDZ is a FAQ: doc.freenas.org/index.php/FAQs You can add disks to non-raid volumes, though. – Roland Smith May 6 '12 at 11:03

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