RAID 0 vs No RAID (Reliability)

[MBrown]

I was thinking of picking up a second hard drive and trying out RAID for the first time. I wanted to do RAID 0 because it is supposed to be fast. But then I have read that it is very easy to lose all of your data if something bad happens. As far as data loss is concerned is it worse than just having one hard drive without RAID or is it just worse that the other RAID configurations.

 

[cmbehan]

It's actually worse than a single drive because if you lose EITHER of the two drives or the RAID controller/configuration, all data is lost....but it is quicker.

 

[MBrown]

Originally posted by: cmbehan
It's actually worse than a single drive because if you lose EITHER of the two drives or the RAID controller/configuration, all data is lost....but it is quicker.

So should I just go and buy a bigger hard drive?

 

[RebateMonger]

Originally posted by: MBrown
So should I just go and buy a bigger hard drive?

I suggest buying a bigger hard drive.....and putting it inside an external USB housing and using it to make periodic backups of any data you don't want to lose. ALL HARD DRIVES FAIL EVENTUALLY. The odds are about 7% per year. Some fail within a few days and some last ten years. As long as you have backups, you can use RAID 0 or no RAID at all. If a drive fails, just get a new drive and restore your data from your backup.

 

[theYipster]

I wouldn't put this in to the perspective of what's "best" or "worst," because RAID-0 may be a great option for some, and not for others... Basically it's a question of RISK.

Keep in mind that Hard Drives fail with greataer frequency than other PC components due to their mechanical operation. In a single HD non RAID setup, if your hard disk fails, it fails and you loose your data. In RAID-0, you take two hard drives and combine them such that they're treated as one. In this setup, when data is written to the hard disks, the data is split by the RAID controller, and half is written to HD1 and the other half is written to HD2. Therefore, if one hard drive goes bad, you loose your data across both.


RAID-1 takes two hard drives and mirrors the data between them. This provides for better safety / lower risk vs. a single non raided drive, because if one drive goes bad, you can jump to the second drive which is just a copy of the data on the first drive.

More advanced RAID combinations allow you to mix and match striping and mirroring across more than two drives. RAID 10 (or 0+1) takes four drives (or multiples of 2 thereof) and provides a combo RAID-0 RAID-1 solution. RAID-5 can give you a combo solution with three drives, using the third drive to hold parity information in case you need to restore from a drive failure.

Mark.

 

[yuppiejr]

Honestly, a single Raptor will have a lower rotational latency meaning much faster access times than even a pair of 7.2k drives in a RAID0 array. By running a RAID0/strike set of 2 drives you are also doubling you chances of a drive failure and the resulting data loss. For a boot/OS drive, latency is king and there is simply no way to overcome the latency disadvantages of 7.2k RPM vs single 10k/15k drives even when you stripe a pair of them.

That said, there will be some small improvement in latency and a HUGE advantage in raw transfer performance with a RAID0 stripe set of 7.2k drives so if you can tolerate the risk it should net you an advantage over your single drive setup.

 

[theYipster]

In my view, RAID 0 is best when you want the simplicity of a large single volume. I've always considered the speed aspects secondary. On the other hand, I've always found raptors to be noisy and stupid -- absolutely not worth the price premium paid for such a small drive. If you absolutely depend on latency and access times, such that a 7.2K drive won't cut it, then you might as well consider SAS. In addition to the 15K drives, you get the added benefit of server-grade hardware robustness.

Mark.