MSA Drive Configuration Question

[BR734009]

I currently have an MSA1000 with an array consisting of 36 GB 15k drives. Can I add a 72 GB 15k drive to this array or do I need to stay consistent and add another 36 GB drive?

Thanks.

[Uwe Zessin]

You can add a larger disk drive, but the additional space will not be used.

[BR734009]

That's kind of a waste then. So basically all of the drive in the array need to be the same size, correct?

[Uwe Zessin]

Yes, some capacity is unused - a SmartArray controller uses fixed formulas. No, as I said: the disk drives need not be the same size - it will work with a larger disk drive.

You can even use this as a feature to enhance the size of a disk array. Rip out one disk and replace it with a larger one. Wait for the rebuild to finish before you swap the next disk. After the last disk has been replaced you see that now you have won additional free space in the disk array.

[BR734009]

Sorry, I'm a bit confused now.

With my current array of 36 GB drives, what would happen if I added an 72 GB drive and expanded the array onto that drive? Would it utilize the 72 GB or would it only use 36 GB?

Thanks.

[Uwe Zessin]

Jason,

the total usable capacity of a disk array depends on the smallest physical disk drive. If you use a single 72 GByte disk drive together with 36 GByte disk drives, then only 36 GBytes of the 72 Gbyte disk drive are used.

Yes, you will 'waste' space, but it works.

[BR734009]

Ok, now I understand. One last question, just to clairify. You mentioned in an eariler post that if I replace all of the drives with 72 GB drives, then my useable drive space will double automatically once all drives have been replaced, right?

Thanks again.