Replacing bad drive in RAID 5 2

[johnmofb]

I have a ML 370 with a bad drive in a RAID 5 array. The drive is an 18 gig SCSI Ultra 320. I don't have any spare 18s, but have a used 36 gig SCSI Ultra 320. Can I hot swap in the 36 to replace the 18 that failed? Does it matter they are different sizes and the 36 was from a different server?

Thanks

John

 

[jfrantz]

John,

You can use a larger disk to replace a smaller disk. The remainder of larger disk will simply go unused.

-Jeff

 

[johnmofb]

Thank you, I thought so. I discovered the bigger drives 10k and the existing 18s are 15k. Will the speed difference matter even for temporary use?

John

 

[spi200]

Hi

The speed difference does not matter and the server will function fine. Just remember that if you put a slow 10K drive to replace a 15K then all the drives in the RAID set will be affected and you will take a perforamce hit upto 33%.
Swapping a 15k in palce for an older 10K should be no problem.


Regards



Dave

 

[johnmofb]

I ended up finding a 15k and plugged it in. Every thing is fine. I knew in theory it should all work, but in 11 years I never had a drive go bad in any of my RAID arrays. So the theory vs real life, made me want a second or third opinion.

Thanks,

John

 

[sreed53]

Followup Question on this thread.

If I over time replace all the drives in the array with larger drives, say going from 250 to 750 Gb, will the array start using the upgraded space when the drives are again all upgraded ??? Why do that ??? Because I really don't have the cash at this time to purchase a new NAS box...... Obviously if the idea won't work I go back to saving for it but .........

Thanks

 

[JG5]

sreed53,

I have done what you are describing several times. A few things to keep in mind though. Make sure you are using a current array controller (I've only done this on the 6x series of HP controllers) and definitely make sure the firmware and drivers are up to date on the controller (and firmware on the drives). Swap 1 drive, let it rebuild completely. You won't see the extra space until all of the physical drives in the array have been swapped and rebuilt. Also, don't trust the Insight Manager page for the status of the drive re-builds - check the ACU to make sure. You definitely don't want a double drive failure.

Good luck - hope this helps.

 

[WDelroy]

How does this scenario play out if there are multiple partitions? What partition will resize or how can you resize the partition sizes after the rebuild?