Quote from obarthelemy on August 20, 2011, 18:29
@abishur why raid 5 ? raid gives higher performance, higher capacity, and higher availability. For a home NAS, you don't really need performance (you need performance not to suck, but not to be up there), and you don't need high availability. As far as capacity is concerned, I find I'm fine with a single 3TB HD, and another one for backups, which are vastly more important than anything RAID offers, and RAID sure doesn't replace backups, and takes up a lot of space, power, and money.
Well I like RAID 5 for several reasons, but it really boils down to I'm planning on using it for an internet accessible archive for family photos/videos/misc. As such I need it to both have a large capacity, have data redundancy, and have high availability . Yes RAID 1 will provide for redundancy, but that means every time I want to expand my RAID I need to purchase 2 new hard drives, which as you stated is fine with you, but is not fine for me it's a tremendous waste of money for me, especially has the whole thing grows. With RAID 5 however, all I need to do is slap a new hard drive in there and it takes care of the rest (ah the beauty of RAID 5).
Also RAID 5 does replace backups, that's the whole point of RAID 5. When one hard drive goes down, you swap it out and then it rebuilds the hard drive based off the information in the other drives. I can start off doing this with three drives. This is only a single additional drive than what you're suggesting and a single drive doesn't take up a lot more space, power, or money. Especially when it's coupled with the r-pi. A good multidrive RAID 5 enclosure with the r-pi equals savings as I no longer need a power hog PC running all the time. Plus with RAID 5 I get the added benefit of getting more storage capacity than you do with just RAID 1.
Dear forum: Play nice