topic Re: RAID questions in ProLiant Servers (ML,DL,SL)

RAID questions

Octahedron — Tue, 12 Jun 2007 11:37:48 GMT

I have a DL360 G3. I see in the RAID config when building the container that the RAID 1+0 option is available? Is it true that you can do this or a 0+1 with only two drives?

If so, could it be possible to do this on a DL380 with 3 drives or is it only possible with 2 or 4 drives? (Assuming the 2 drive method is possible)

Re: RAID questions

GB Tek — Tue, 12 Jun 2007 12:13:56 GMT

Unless the definition has changed, RAID Level 0+1 requires a minimum of 4 drives to implement. The DL360G3 can only hold 2 drives. I'm not sure how it would be possible to do RAID 0+1 on the DL360G3. It is possible on the DL380 as long as you've got 4 drives.

Re: RAID questions

Octahedron — Tue, 12 Jun 2007 13:44:44 GMT

Seeing as how i asked about a 1+0 vs. 0+1 (yes there is a difference) the older DL360 machines if you build the RAID container you will notice that the option for 1+0 is there. This is why i was asking this question.

Thanks

Re: RAID questions

Octahedron — Tue, 12 Jun 2007 13:52:21 GMT

If you look even at the new configs for the DL320 G5 it supports a 0+1 with SATA drives.

Thanks

Re: RAID questions

Heironimus — Wed, 13 Jun 2007 10:09:50 GMT

0+1 and 1+0 require at least 4 drives, but I vaguely remember hearing somebody say that in the SmartArray setup you could configure a 2-disk array with that and it would actually run as a RAID1.

I don't think the SA controllers support building a composite RAID level with an odd number of differently-sized drives, and I wouldn't recommend it even if they did. You should use at least 4 drives for a 0+1 or 1+0 array.

Re: RAID questions

Joyson Noronha — Tue, 25 Sep 2007 14:01:11 GMT

Hi Octahedron,

DL360 G3 Server Model has an Integrated Smart Array 5i Controller.

It Supports RAID 0, RAID 1 & RAID 0+1

RAID 0+1 Requires Minimum of 4 HDD's

However the Server Supports 2 Internal HDD's
& If you Want to create RAID 0+1 & Then would have to Use an External Storage Device Like MSA & Use the Internal Controller to Configure RAID.

***********************************************

- You can Perform RAID 0+1 On DL380 G3 As it has the Same Controller like DL360 G3

- You will However Require Minimum of 4 HDD's to do it

-Joyson

Re: RAID questions

David Claypool — Tue, 25 Sep 2007 14:20:23 GMT

No, No, NO!

RAID 0 = striping
RAID 1 = mirroring
RAID 1+0 = striping and mirroring

Even with 2 drives, the default SmartArray options are either RAID 0 or RAID 1+0.

Beyond 2 drives it always must be an EVEN number of drives to get RAID 1+0.

An ODD number of drives can be configured as RAID 5 or RAID 1+0 with ONLINE SPARE.

Re: RAID questions

Joyson Noronha — Tue, 25 Sep 2007 15:21:22 GMT

Hi,

Below is the Link & Explanation on RAID Requirements

http://en.wikipedia.org/wiki/Redundant_array_of_independent_disks

In Old Servers it would Give you the Option to Select RAID 0+1 in Array Configuration Utility But the Server would Configure RAID 1 Automatically if You are Using 2 HDD's.

But on New Model Server This Options would Only be Given if You are Using the Require No of HDD's

-Joyson
(The Above Information Provided is Tried & Tested)

Re: RAID questions

David Claypool — Tue, 25 Sep 2007 16:33:18 GMT

Wikipedia is a wonderful thing but it is far from unimpeachable. Please see the attached screenshot from a working ProLiant server's Array Configuration Utility that clearly shows RAID 1+0 with 2 drives and a single controller.

Re: RAID questions

Joyson Noronha — Tue, 25 Sep 2007 20:05:21 GMT

Hi David,

The Fact Does not Change, Even If You Delete My Article from Forum.

I Appreciate , The Screenshot provided You. But Wanted to Explain you What it Actually Meant.

Here are the Hp Articles Supporting Answer.

http://docs.hp.com/en/J6369-90050/ch02s06.html?btnNext=next%A0%BB

The 5i & 6i Controller Which States RAID 1+0 is Mirroring

PlEASE REFER TO HP SMART ARRAY 6I USERGUIDE PG42,43 & 44, Which Explains the Fact.

For Further Confirmation Can Contact Hp Proliant Server Support 1800-633-3600.

-Joyson