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A3700A HP12 array questions

 
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Peter Godron
Honored Contributor

A3700A HP12 array questions

Have inheritet a A3700A HP12 12 disk array.
Currently it prsents as a solid block of 1 big disk, rather than 12 individual disks.

Although it defeats the array idea, is there any way of splitting the disks, so I can assign 1 volumne group to 1 PHYSICAL disk?

I know I can create LUN, but I want to mount 1 physical disk at a time.

Thanks
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Sanjay_6
Honored Contributor

Re: A3700A HP12 array questions

Hi Pete,

Check out page 100 onwards of this manual,

http://h200001.www2.hp.com/bc/docs/support/SupportManual/c00269878/c00269878.pdf

Hope this helps.

Regds
Peter Godron
Honored Contributor

Re: A3700A HP12 array questions

So as I suspected, the physical disks are all presented as one big chunk, which can then be split into logical drives.
These drives are split across a number of disks.

My problem is that I WANT to put one oracle database (all tablespaces etc) onto one physical disk, so that if one disk fails I only lose 1 database.
I know that oracle recommends splitting across a number of disks for performance, but the user is more concerned with the problem of losing more than one database.

Regards
A. Clay Stephenson
Acclaimed Contributor
Solution

Re: A3700A HP12 array questions

Then find yourself another array because this one won't do it. The whole point of the AutoRAID is that you have no control over the physical placement of the data --- and you don't need it. As long as you are using both controllers and these are on separate SCSI buses, you don't need to be concerned about disk failures because the array will take care of that for you. I've used these many of these arrays over the years and have never lost a single bit of data.

I suggest that you actually setup 2 LUN's of equal size and put them in 1 VG. LUN0's primary path should be through controller X (alternate Y) and LUN1's primary path should be through controller Y (alternate X). You then stripe each LVOL in this VG across both LUN's in 64K chunks. This will fully utilize both external SCSI boths and all four internal SCSI buses. If you allocate no more than 50 of your total capacity as LUN's, the array will remain in RAID 1/0 mode for all data and you will be quite surprised at how well these old gals can perform.

If you allocate most of the capacity as LUN's then you will have a dog.
If it ain't broke, I can fix that.
A. Clay Stephenson
Acclaimed Contributor

Re: A3700A HP12 array questions

Ooops, I'm an idiot.
"If you allocate no more than 50 of your total capacity" should be "If you allocate no more than 50% of your total capacity".
If it ain't broke, I can fix that.
Peter Godron
Honored Contributor

Re: A3700A HP12 array questions

Thanks for all the info.
Will now run with RAID instead.