Raid O + 1 QnA

[go flames go]

say if someone were to have to 300gb velcoiraptors in raid 0 and then a 640gb backup drive (black) Would it be pointless since when the two velociraptors right it would be slower transfering the data to the 640gb backup drive? In turn it would be a waste? Please reply if I am thinking of this the wrong way or if theres a better solution to that setup. THANKS!

[Jake_HT]

You would use the RAID 0 for your OS and games.. and storage drive for music pictures and movies... because they don't need speed. Why would you be transferring things from your RAID to your storage drive? Just put them on the storage drive from the get go...

And unless you're made of money, the velociraptors are a waste of money, they don't offer the performance to justify the cost, you're better off getting 640 GB Caviar blacks, not much slower, a lot less price, and a LOT more storage. They're the best drive for the money right now.

A 2 drive RAID 0 with a backup storage drive is great for performance and reliability... that's what I'm using right now, and I love it.

[bojangles]

That is not RAID 0+1 gfg. RAID 0+1 is two RAID 0 arrays that are mirrored. Basically if one drive fails in the mirrored RAID 0 array, it's screwed. I would use RAID 0 for your OS/non-important data and your larger HDD for your data.

AC&NC | RAID.edu - RAID Levels - RAID Level 0+1 - RAID 0+1
Nested RAID levels - Wikipedia, the free encyclopedia

[sswilson]

Originally Posted by bojangles

That is not RAID 0+1 gfg. RAID 0+1 is two RAID 0 arrays that are mirrored. Basically if one drive fails in the mirrored RAID 0 array, it's screwed. I would use RAID 0 for your OS/non-important data and your larger HDD for your data.

AC&NC | RAID.edu - RAID Levels - RAID Level 0+1 - RAID 0+1
Nested RAID levels - Wikipedia, the free encyclopedia

Hrmmmmm....

Ok, I'm pretty sure I know what the OP is looking for, and I always thought it was RAID 0+1 as well....... :)

Rather than having a single "storage" drive, he wants to have the non-redundant raid (two raptors) array mirrored onto the single drive.

Been a while since I looked into doing a raid, but I'm pretty sure I remember seeing that kind of setup.

The main question he's asking is if mirroring the array onto the single drive would drag down the speed of the array.

[death_hawk]

Originally Posted by go flames go

say if someone were to have to 300gb velcoiraptors in raid 0 and then a 640gb backup drive (black) Would it be pointless since when the two velociraptors right it would be slower transfering the data to the 640gb backup drive? In turn it would be a waste? Please reply if I am thinking of this the wrong way or if theres a better solution to that setup. THANKS!

That's not technically RAID0+1.
You need 4 identical drivess for that.

That's just RAID0 with a backup.

[sswilson]

But can the RAID0 be directly mirrored onto the single drive in such a way that the array could be rebuilt if one of the drives failed?

[death_hawk]

Like having a RAID0 with a single drive backup?
The controller itself will not do it. You'd have to do something from within the OS.

You can RAID10 (0+1, basically the same...) the 2 VRaps and 2 640 Blacks, but you'd be restricted to the VRaps space and the Blacks speed.

And most times, RAID10 needs a reason to be used. This is the most expensive drive cost wise implementation of RAID. Most times it's used in something like a DB server where you need speed and redundancy.


Honestly if you go for a decent HBA (Host Bus Adapter aka RAID Card) RAID5 or RAID6 is perfectly viable for speed, redundancy and disk cost.
In fact my 3Ware has higher write speeds on parity based RAID (5/6) than it does reads.

[sswilson]

Thanks for the info.

I had another look to see if I coul find what I was remembering and didn't have any luck at all.... :)

I'm still fairly certain that I haven't lost my mind (yet) so I'm starting to think that it might have been some kind of "special" setup from software raid on a particular motherboard I've had in the past.

[Dave510]

RAID0+1 Array or Alternate Raid 0 Backup - EXTREME Overclocking Forums

Conclusion seems to be that:
a.) You can clone your RAID0 partition onto a single drive.
b.) In the event that your RAID0 array fails, you can boot from the single drive with no problem.
c.) You can also clone the data on the single drive back onto a new RAID0 array but the RAID0 array will fail to boot, even though all the data is there

[death_hawk]

A proper RAID0 (ok any RAID) should show up as a single drive to the host OS.
Any proper cloning software should also be able to clone the boot options.

This process isn't automatic in the sense of having all changes written immediatly like a RAID would do.

It's perfectly doable and I guess the 640 would be crippled by the RAID0 since reads on RAID0 should HUGELY outweigh the writes on a 640.