topic Re: Controller RAID 6 ADG - Help Understanding This Setting in ProLiant Servers (ML,DL,SL)

Controller RAID 6 ADG - Help Understanding This Setting

Dave Holtz — Thu, 06 Sep 2007 23:04:21 GMT

I am a DBA trying to understand if we should be enabling RAID 6 ADG on our controllers. What does it mean if RAID 6 ADG is enabled, but our arrays are either RAID 1, RAID 5 or RAID 10? Does enabling RAID 6 ADG only mean that if a RAID 6 array is configured then the Advanced Data Guard kicks in or does that also apply to RAID 1, 5 and RAID 10?

If we are not using RAID 6 should we be disabling RAID 6 ADG on our controllers?

Thanks, Dave

Re: Controller RAID 6 ADG - Help Understanding This Setting

AwadheshPandey — Fri, 07 Sep 2007 00:00:29 GMT

http://h18004.www1.hp.com/products/servers/proliantstorage/arraycontrollers/adg/questionsanswers.html

Re: Controller RAID 6 ADG - Help Understanding This Setting

KarloChacon — Fri, 07 Sep 2007 00:57:05 GMT

hi

also check this documents attached

RAID 6 with HP Advanced Data Guarding technology
RAID level comparison chart (at the end)

my comment
- RAID 5 is faster that RAID 6 but RAID 6 is more fault tolerance
- RAID 6 is highly used on SATA environments when the applications require large capacities

other links (see the attached file in case the links don't work - sometimes happen)

What RAID level is Right for U?
http://storageadvisors.adaptec.com/2005/10/17/what-raid-level-is-right-for-u/

Is RAID-6 made of wood?
http://storageadvisors.adaptec.com/2005/11/03/is-raid-6-made-of-wood/

SATA and RAID 6 â the perfect match!
http://storageadvisors.adaptec.com/2005/11/01/sata-and-raid-6-%e2%80%93-the-perfect-match/

RAID-5: Pining for the fjords?
http://storageadvisors.adaptec.com/2005/10/13/raid-5-pining-for-the-fjords/

I hope this can help you

regards

Re: Controller RAID 6 ADG - Help Understanding This Setting

Dave Holtz — Fri, 07 Sep 2007 13:16:14 GMT

Thanks for the feedback, but I'm more concerned with the impact of having this option enabled when our arrays are not RAID 6.

What does it mean if RAID 6 ADG is enabled, but our array is not RAID 6? Does enabling RAID 6 ADG only mean that if a RAID 6 array is implemented then the Advanced Data Guard kicks in?

If we are not using RAID 6 should we be disabling RAID 6 ADG on our controllers?

Thanks, Dave

Re: Controller RAID 6 ADG - Help Understanding This Setting

KarloChacon — Fri, 07 Sep 2007 17:30:57 GMT

hi

well I dont know if I got your point...

"concerned with the impact of having this option enabled when our arrays are not RAID 6"

you can not disable o enable a RAID level it is not option

"What does it mean if RAID 6 ADG is enabled, but our array is not RAID 6?"

If you have RAID 6 configure it is because you define RAID 6 using at least 4 HDDs and using Array Configuration Utility

An Controller Card for example P400, P800 and others have the capability to create RAID 6 but if you don't need it yo don't use, you can define RAID 0, RAID 1, RAID 5 in your controller so in case (future) you will need RAID 6 you can use your controller to create that RAID 6

"If we are not using RAID 6 should we be disabling RAID 6 ADG on our controllers?"
RAID 6 = Advance Data Guard
The only way to know if you have RAID 6 "configure" is using Array configuration utility or array diagnostic utility

------------
if you have in this moment an array level with RAID 6 and you want to recreate(not disable) another level RAID 5 for example you will lost all the data(first a backup)

regards

I hope this can help you
any other question just let me know

Re: Controller RAID 6 ADG - Help Understanding This Setting

Dave Holtz — Fri, 07 Sep 2007 21:23:19 GMT

Let me try again. Open HP Array Configuration Utility. Select a controller such as a Smart Array P800. To your right is a windows called Common Tasks. Under this window select More Information. Within this screen you see items on the left such as Bus Interface and Controller Location. Below Controller Location is RAID 6 (ADG) status. To the right the status indicates "enabled". Since it indicates enabled I assume it can also be disabled. This RAID 6 (ADG) status is independent of our actual RAID configuration. At this point is where my previous questions come into play. Hope this explains things better.

Thanks

Re: Controller RAID 6 ADG - Help Understanding This Setting

Blazhev_1 — Sat, 08 Sep 2007 06:06:14 GMT

Hi,

RAID6 enabled means that if you want, you can configure RAID6 logical drives. You can't disable it. It is explicit written, because on most Smart Array Controllers(e.g. P400) you must buy optional BBWC to support RAID 6.
This message indicates that on this controller RAID6 is supported and if you want you an configure it. I don't think you can't disable it! Since you don't have logical drives with ADG, you have nothing to do with ADG.

If I missed something, ask :)

Regards
Pac

Re: Controller RAID 6 ADG - Help Understanding This Setting

KarloChacon — Sat, 08 Sep 2007 10:57:56 GMT

hi

Pac is right

for example I have a P400 that has that option disabled why? because my P400 has 256 MB by default it means that does not have the option to create RAID 6 so if I upgrade my P400 controller with more BBWC I will have the RAID 6 ADG option enable because I will have the possibility to create RAID 6 whenever I can

in your case if you see that option (that information enabled) is because yur controller has the option to have RAID 6

dont worry if that is enable it does not affect performance on servers.

regards

Re: Controller RAID 6 ADG - Help Understanding This Setting

Dave Holtz — Mon, 10 Sep 2007 08:26:18 GMT

Thanks. That's the answer I was looking for.

Dave

Re: Controller RAID 6 ADG - Help Understanding This Setting

KarloChacon — Mon, 10 Sep 2007 09:10:58 GMT

hi

don't forget assign some points next time

regards

Re: Controller RAID 6 ADG - Help Understanding This Setting

Dave Holtz — Mon, 10 Sep 2007 09:15:28 GMT

I'm not seeing the dropdown points menu. Where is it?

Re: Controller RAID 6 ADG - Help Understanding This Setting

Dave Holtz — Mon, 10 Sep 2007 09:17:43 GMT

I must be blind. I see it now.

Re: Controller RAID 6 ADG - Help Understanding This Setting

KarloChacon — Mon, 10 Sep 2007 09:19:03 GMT

hi

weird uh??

see the attached file

anyway nerver mind

regards