3-dimensional RAID array?

[fury]

Has this ever been attempted? Better yet, is it possible?

Example: You want the extreme performance of striping but also don't want to lose the whole array when one drive fails. So you have 2 channels, each with 2 drives on it. In each channel, you want the two drives to be redundant copies, and then put the two arrays into an array of its own, a striped array.

 

[outside looking in]

Yes, that is called RAID 1+0, or some people call it RAID 10.

It is effectively just what you said... four drives, with two stiped pairs of redundant drives.

There is also RAID 5, which uses three drives. You can think of it as two striped drives, and a third as a type of error correction. I think it uses a difference bit format, but I'm not sure about that. It's more complicated than just two striped drives and a backup though, since I believe that in RAID 5 you can rebuild the data from any two of the three drives. A kind of distributed error correction/striping. This is supposed to give the data redundancy of RAID 1 with nearly the same performance as RAID 0, while only requiring three drives instead of four (I hope I didn't get 0 and 1 backwards).

I think some IDE RAID cards should be able to do this, but I think SCSI RAID 5 capability gets kinda expensive (relative to "non expensive" SCSI RAID cards ).

 

[ipmoof]

The skinny on RAID.

I think Sam was talking about some RAID 5 array he had planned last time I spoke to him on MSN.

 

[PostCode]

Ok. Not coming from me mind you, but a few others I know say it's RAID 1+0 or 10 your looking into here.

mirror(1) before stripe(0)


http://www.adaptec.com/worldwide/product/markeditorial.html?sess=no&cat=%2fTechnology%2fRAID&prodkey=raid_10_alternatives

 

[Jeslek]

We do it in our Sun Enterprise servers.

 

[dan]

mmm

We do it in our Sun Enterprise servers.

mmm... i was hoping for a starfire, but we got a pair of 6500's instead...

and the last company had a 250 which did nothing but serve mp3's.... yum yum

 

[fury]

We do it in our Sun Enterprise servers.

Really? Normal people usually prefer to do it in their bedrooms or in the back seat of a car.