Upgrading Drive's To Larger Capacity

[Thoams J Mattauch]

I have a Proliant ML370 with a Smart Array 431 Controller with 3 18GB Drives connected in RAID 5. I have purchased 3 72GB Drives to upgrade to. My question is, can I upgrade by placing one 72GB drive in, allowing it to stripe and mirror, pull one 18 out, and so on, then will the array resize to recognize the 72GB drives afterwards?

[Iain Marshall]

I'm afraid you idea won't work. If you replace an 18Gb disk with a 72Gb disk, the 431 controller will only stripe across 18Gb of your 72Gb disk, making the remaining space unusable. The same will happen when you replace the following 2 drives, so you won't have any more space. I have had the same situation a few times (and I have it coming up again), and I've just done a complete rebuild.

Take out the old disks, and label them with the slot they came out of so you can put them back in later if required.
Put in the new disks, reinstall the operating system, backup software and do a restore. The good news that if you have problems with the restore, or whatever, you can put the old disks back in the same slots and you have your server back online. This will give you time to review the problems you had. I've never had to resort to this though.

Good luck.

Iain Marshall

[Janine Bertolo]

Actually you should be able to make this transition, although we do not recommend pulling and replacing hot-plug drives live unless they've failed. You can down the server and replace and rebuild one drive at a time.

Keep in mind that, while the array is being rebuilt to the bigger drive, if another drive fails on the array you will lose the whole set, so having a recent backup is always advisable.

True, the existing logical drive on the array will remain at 18GB, but once all the drives in the set are replaced, you can create another logical drive using the resulting free space with the Array Configuration Utility.

The Operating System will not see the free space until it is configured as a logical drive, but this does work.

Your operating system will determine whether extending the existing logical drive or adding another is the best option. Adding a second logical drive is the safest option to ensure the OS is able to see the space.

Cheers,

Janine