General RAID Array Question.
 

I have a RAID 5 array consisting of 3 disks. One disk has failed. The three disks were IBM Microstars, 18GB. Unfortunately I cannot find another duplicate to replace the failed drive with.

Does a replacement drive for an array have to be exactly the same? I understand that if it's larger the array won't use the extra space -- nor will I be able to. I also understand that if the performance of the new drive is subpar as compared to the other members of the array that the array performance will suffer.

However this array has been in place for nearly three years and I rather doubt that I can find an exact drive to match it with, which is what I've always been told I should do.

Is it possible to purchase a 20Gb or 38.4Gb drive and use it in the array?

(The RAID card is an Adaptec 2000S.)

Thanks.

Alright, since nobody else has stepped up to the plate...

In a nutshell, yes, you should be able to plug a larger drive in just to keep the array alive, and yes, you will not be able to use the extra storage capacity in any way, shape, form, or fashion. That said, go to Adaptec's website and do a little searching about the specs of the card. Calling technical support would be a waste of your time, because they will tell you they do not support any configurations except identical drives. Check the documentation for any potential hazards, and if you don't see one, then give it a try. On a drive rebuild, the other drives should only be read from while the new drive is written to. So, a worst case scenario would leave the new drive dead, but the original two intact.

I would suggest you strongly encourage management to shell out the cash to upgrade the array completely seeing as how replacement parts are no longer available, and it seems the life expectancy of the drives could be coming to an end.

Side note: from personal experience, I was having problems with an Adaptec IDE RAID controller, I had 3 drive of 40GB each, all made by Western Digital, and all bought off the same shelf at a local store. When I emailed technical support, they washed their hands of the problem because one drive had a model number differing by one digit (probably from a different manufacturing load). They were identical drives, but I have a feeling they wanted to distance themselves from the part because there were a number of people I found that weren't happy with it.

Thanks Dark Helmet.
 

(LQ needs to add a helpfulness rating, sort of like GameDev has. It gives me great satisfaction to be able to rate someone as helpful and at least help them in *some* way other than, "Thanks.")

The upgrade them all plan was suggested by management (can you believe it? :)) this evening when the difficulties with the replacement drive were brought to light. I'm still very curious about this so I think after we backup the drive and before we migrate it to a new set I'll plop in a larger drive and see how it goes.

It will be useful information for the future.

Thanks again.