Im working at a company at the moment who uses an 8TB NAS RAID. It is RAID 6. (We are a video editing company). The data on the RAID is very important, which is why I think they originally went with RAID (for the parity striping etc). However, will this slow everything down> Just reading up about RAID 6 and it apparently doesn't offer that many advantages, but DOES slow the system down a fair bit because if the amount of algorithms RAID6 needs. What would you guys suggest is the best for an 8TB (8 HDDs) RAID for video editing?
Our STARDOM ST8-U5 (8 bay mini-SAS) DAS with a ATTO R680 card will give you 700MB/s Read/Write Speeds in RAID 6. While it's not a cheap solution, it's more cost effective than others out there & is field proven, with end users such as NBC using it. The beauty of the ATTO R680 card is you won't lose much speed if a drive fails and you need to rebuild.
It seems like you've done some research on RAID 6. We take it you're editing in Final Cut Pro?
RAID 6 is the best choice when editing, (when you have the capacity to do so). Always get more capacity Larger drives than you think you'll use, trust me.
With RAID 5 if you have a drive fail and a 2nd drive fails in the rebuild process, you'll lose the whole array in RAID 5.
In RAID 6 you can have 2 drives fail and still be protected.
I didn't catch the "iMac" part, that does change things. If he wants/needs appreciable speed in RAID 6 there aren't many options. We do have a 5 bay with RAID 6, but with FireWire 800 speeds it'd still be too slow to edit uncompressed HD. Maybe Bob Z or someone else has a suggestion.