RAID 10 anyone?

[kd6icz]

The new motherboard I purchased is a Supermicro server grade board that supports RAID 0,1,5 and 10. I am debating between RAID 0 or 10.

I could do without the extra 6TB in favor of redundancy but I don't know much about it.

Thoughts?

[UCBearcat]

Based on your description, it sounds as though you have 4 x 3TB drives. I'm going to work on this assumption.
Your choice of RAID is solely dependent upon what you're trying to accomplish. If you intended to put a bunch of data on this storage that would be hard to reproduce (i.e. tons of DVD rips, etc.), then RAID-0 is a bad bad bad idea. Lose just a single disk and you're screwed.

Based on my understanding of a RAID-10, it is essentially a RAID-0 mirrored to a second set of RAID-0 drives. RAID-10 does give you fault tolerance, however your fault tolerance is still just one disk in your scenario.... which is the same amount of fault tolerance as a RAID-5. My understanding is such that if you lose a single disk - no problem. That RAID-0 is essentially broken and ignored until the bad drive is replaced. The remaining RAID-0 keeps going. But, if you lose a disk in that remaining operational (mirrored) RAID-0 before the bad disk is replaced and rebuilt, then you lose it all.
Now.... with a RAID-5, you're only giving up a single drive to parity. With the RAID-10, you're giving up half of your spindles (drive space) to fault tolerance that is no better than the fault tolerance of a RAID-5... which will only cost you one of your spindles.
If this were me, and I didn't want to lose everything in the event of a single drive failure AND I wanted to maximize disk space... I'd choose a RAID-5.

I think the only thing that the RAID-10 would give you is slightly better performance in terms of Read/Write operations. I'm basing this on the fact that RAID-0 generally performs a bit faster than a RAID-5. BUT - in a home media server, I don't think you'd really notice the performance gains you'd get from a RAID-0.

Hopefully someone else on here can jump in and give their 2 cents - or correct any mistakes that I've made above.

Edit: After re-reading my post, I believe my explanation of a RAID-10 is inaccurate. I think I am confusing RAID-10 and RAID-01.

[Doctor Feelgood]

UCBearcat - I think you are on the money with RAID 10... Commonly 4 drives, a pair of drives is mirrored and the striped to the other pair of drives.

I think we need to know what your drive selection is?

I pretty much just use RAID 5 since it is quick enough and gives me fault tolerance of one drive (and hot swappable in my setup).

[kd6icz]

Ok. I'm using four 6TB WD Reds. I want to say that in addition to what's stated above, RAID 10 will also continue to function on the working pair in the event of a single drive failure. Where RAID 5 will be standing by waiting for the bad drive to be replaced.

RAID 10 is just RAID 1 with two pairs (vs. 2 single drives).

Does this sound right?

[kd6icz]

To put it more simply:

RAID 0 would give me 24TB no redundancy

RAID 5 would give me 18TB with redundancy but would be non operational until bad drive is replaced

RAID 10 (1+0) would give me 12TB with two identical arrays and would still function if one array failed.

Sound right?

[Doctor Feelgood]

Sounds about right, except it shouldn't be non-operational if you lose a drive in RAID-5... It should just be degraded.

[seajunk]

I used to run Raid 10 for years on a gaming system before SSD's came along. It was easy to setup through the bios, the performance was Raid 0 equivalent, largely maintenance free and never had a disk failure. It was a fun geeky thing to do when i was younger but i wouldn't recommend it now. For a gaming system, go SSD, for HTPC applications you dont need the performance. I get the redundancy theory in the case of disk failure but whats your back up strategy in the case of catastrophic failure like your house burns down or the pc/nas is stolen?

[kd6icz]

I used to run Raid 10 for years on a gaming system before SSD's came along. It was easy to setup through the bios, the performance was Raid 0 equivalent, largely maintenance free and never had a disk failure. It was a fun geeky thing to do when i was younger but i wouldn't recommend it now. For a gaming system, go SSD, for HTPC applications you dont need the performance. I get the redundancy theory in the case of disk failure but whats your back up strategy in the case of catastrophic failure like your house burns down or the PC/nas is stolen?

I've thought about the point your making as well. The first thing that I ask myself was if it's really necessary to have redundancy for recorded TV. Its just TV for Christ sake! But then that kind of negates the whole point of being able to save entire series of TV shows... Right? I mean I would certainly rather have 24TB over 18TB. But every time a drive would die I would be starting over.

Granted, hard drives are pretty reliable these days. But it only takes one failure to mess up your relationship with the Mrs... So that's why I was leaning toward the RAID 5. But of course the motherboard could die. The boot mSATA drive could die. There are other failure points for sure.

[seajunk]

I agree, keeping that relationship is paramount. Try the Raid 5 and let us know how it goes.