Disk Enclosures
Showing results for 
Search instead for 
Did you mean: 

Auto raid 12h disk management

Go to solution

Auto raid 12h disk management

Hi all,
Can an auto raid 12h that has some 18.2gb disks take 2 additional disks of 38gb each? what is likely effect if any?
Please I need the solution as soon as possible.

Vincent Farrugia
Honored Contributor

Re: Auto raid 12h disk management


We had customers who added two 36Gb disks to their autoRAID without any problem. There is a catch though. You must upgrade your controller firmware to HP54 or higher in order for the 36Gb disks to be recognised. Here for more information:


Also, if you still have old fans, you have to upgrade to the new fans, since the 36Gb disks are 10,000rpm disks. Here for more info:


Here for info n how to upgrade firmware:


Tape Drives RULE!!!
Brian M Rawlings
Honored Contributor

Re: Auto raid 12h disk management

As Vincent says, it is possible to add two or more 36GB drives. Provided you have the latest firmware (I would suggest HP62, the latest I know of), you should be fine.

What is not as clear is what you will see from this. The reason you have to add at least a pair of larger drives is that the 12H likes to stripe data across several spindles, and for protection it MUST have at least two different drives that it can use for a given block.

So, it will treat the "bottom half", the first 18GB of each drive, as an 18GB drive, with multiple stripe size and mix and match data from any of the other 18GB drives. The "top half" of each 36GB drive, however, will only be able to be mirrored to the top half of the other, so that space will only be mirrored (RAID 0/1), never RAID 5, unless three or more 36GB drives were used.

It all works, you just might not get as much storage out of the two drives as you think that you might. It is a good idea, and makes much better use of the very limited number of disk slots in the 12H arrays. Do pay attention to the points Vincent made, particularly about the fans. If you don't know if you have the high-speed fans, you can tell from the little "fan shaped" logo on them. The normal fan modules have a flat logo, where, on the high-speed fans, the logo is sort of rounded, bulging out as though the extra wind is inflating it or something. You can't easily tell by looking, but run your finger over the logo, and you can instantly tell flat from 3-D rounded.

Best Regards, --bmr
We must indeed all hang together, or, most assuredly, we shall all hang separately. (Benjamin Franklin)

Re: Auto raid 12h disk management

Hi all,
Thanks for the info,will work on that.
Best regards.