Z87 Pro4 and Raid 10?

[rs301]

Though I've been working with computers for forty years I just made my first venture into RAID. After reading the specs on my MB and reading lots of Internet information I decided to change my Raid 1 array to Raid 1+0 array. After dropping $250 for more drives and spending a weekend creating fresh system images it was finally time to power it up.

I made all the updates to the BIOS and continued on to the Raid configuration menu being forewarned that my next selections would send all the existing data on my drives into oblivion. I scrolled through the Raid configuration choices until I got to what I wanted to see; "RAID 10 (RAID 0+1)." WHAT!!!? That's not Raid 10! That's Raid 01! Surely just a translation error.

Not given the 1+0 choice I wanted, I blindly kept on creating the volume only to be disappointed. Indeed it was an array of 2 striped discs and 2 mirrored discs, Raid 0+1, not Raid 1+0. Just to add insult to injury, my 4, 1TB WD drives had been turned into a single 1.83TB volume. I lost the capacity of 2 drives, not 1 as should have been the case with a Raid 1+0 array.

I don't understand the reasoning behind not offering the choice of a real, more fault tolerant, more storage friendly, Raid 1+0 array. Not to mention all the specs calling it out as a Raid 10 when it is a Raid 01. IMO, a Raid 0+1 array has limited purpose on a desktop computer. It may be a tad faster but certainly not as secure.

I hope there's someone out there who can tell me where I went wrong.

[parsec]

Re: Z87 Pro4 and Raid 10?

I assume you are using the Intel RAID capability of your board, with the Intel RAID IRST driver?

This is Intel's description of RAID 10 from the help documentation available from the Windows IRST GUI:



It sounds like you wanted a RAID 1 + 0 as described here:


RAID 0+1: striped sets in a mirrored set (minimum four drives; even number of drives) provides fault tolerance and improved performance but increases complexity.

The key difference from RAID 1+0 is that RAID 0+1 creates a second striped set to mirror a primary striped set. The array continues to operate with one or more drives failed in the same mirror set, but if drives fail on both sides of the mirror the data on the RAID system is lost.

RAID 1+0: (a.k.a. RAID 10) mirrored sets in a striped set (minimum four drives; even number of drives) provides fault tolerance and improved performance but increases complexity.

The key difference from RAID 0+1 is that RAID 1+0 creates a striped set from a series of mirrored drives. The array can sustain multiple drive losses so long as no mirror loses all its drives.

Intel's implementation of RAID 10 is RAID 0 + 1, given this information:



The Intel RAID 10 volume size is 2/n, where n is the number of equal capacity drives used. So the volume size you get is normal for that RAID 10.

Intel's RAID is supposed to follow the SNIA standard for RAID. I don't see any one step method of creating the RAID 10 (1 + 0) you want. You could try starting over and create two RAID 1 volumes of two drives each, and then try to create a RAID 0 volume of those volumes. I don't know if that will work.

[rs301]

Re: Z87 Pro4 and Raid 10?

I assume you are using the Intel RAID capability of your board, with the Intel RAID IRST driver?

This is Intel's description of RAID 10 from the help documentation available from the Windows IRST GUI:

[ATTACH]6305[/ATTACH]

It sounds like you wanted a RAID 1 + 0 as described here:


RAID 0+1: striped sets in a mirrored set (minimum four drives; even number of drives) provides fault tolerance and improved performance but increases complexity.

The key difference from RAID 1+0 is that RAID 0+1 creates a second striped set to mirror a primary striped set. The array continues to operate with one or more drives failed in the same mirror set, but if drives fail on both sides of the mirror the data on the RAID system is lost.

RAID 1+0: (a.k.a. RAID 10) mirrored sets in a striped set (minimum four drives; even number of drives) provides fault tolerance and improved performance but increases complexity.

The key difference from RAID 0+1 is that RAID 1+0 creates a striped set from a series of mirrored drives. The array can sustain multiple drive losses so long as no mirror loses all its drives.

Intel's implementation of RAID 10 is RAID 0 + 1, given this information:



The Intel RAID 10 volume size is 2/n, where n is the number of equal capacity drives used. So the volume size you get is normal for that RAID 10.

Intel's RAID is supposed to follow the SNIA standard for RAID. I don't see any one step method of creating the RAID 10 (1 + 0) you want. You could try starting over and create two RAID 1 volumes of two drives each, and then try to create a RAID 0 volume of those volumes. I don't know if that will work.

Thanks for the reply. Your research was definitely more accurate than mine. I must have read a dozen articles, many forum posts and watched 3 or 4 YouTube videos about Raid arrays and never realized there was any ambiguity in the definition of Raid 10. It never occurred to me to look at the Intel website. I knew there was an Intel Raid driver on the utilities disc that came with the motherboard but I'm using whatever Raid implementation is on the MB firmware. That code is apparently Intel also. I guess I thought it was a BIOS function. Live and learn.

I don't know if your idea to create a faux Raid 1+0 would work or not. I have a hunch it wouldn't. I recall reading several forum posts where they were trying to create Raid arrays that weren't really supported by the hardware or software they were using. I don't recall all the details but it seems to me they all failed at the creating the final volume stage. I didn't pay real close attention as I knew my board supported Raid 10, which is just what I wanted.

Since creating a Raid 1+0 array was really a learning experience and not a necessity I just went back to my original Raid 1 array and now have 2 backup discs. The backups are probably more important anyway.

Thanks for your research.