topic Re: AutoRAID in Disk Enclosures

AutoRAID

U.SivaKumar_2 — Wed, 30 Oct 2002 06:55:20 GMT

Hi,
We have a AutoRAID 12H box with Firmware version HP60 . With below Disk ombinations.
2*36GB HDD
4*9GB
6*18GB

Now we want to replace 2*9GB with 2*36GB. We replaced 1HDD with 9GB. Array rebuilded and status is READY.

Now If I disconnect the HOST (SHUTDown the HOST ) array state becomes "Balancing".

Can I replace the other HARD DISK at this stage?

Please don't move this thread for 1 hour anywhere.

regards,
U.SivaKumar

Re: AutoRAID

Vincent Farrugia — Wed, 30 Oct 2002 07:44:36 GMT

Hello,

No, harddisks on the AutoRAID should be removed when the array is ON. Just as you did before.

Why would you want to shutdown it?

HTH,
Vince

Re: AutoRAID

Eugeny Brychkov — Wed, 30 Oct 2002 07:56:26 GMT

Hello,
12H should start balancing after you insert new disk and it was included to a list of disks (immediately included if autoinclude option is set). Do not remove any other disks until balancing will be finished.
I recommend to do disk replacements one by one:
disk removed->rebuild->disk replaced->balancing
I guess there can be a way to make this process faster (for example, not waiting for rebuild to finish, but immediately insert new disk).
Do not forget to make full backup before doing anything to AutoRAID 12h. Just to be sure you're secure with your data
Eugeny

Re: AutoRAID

Rainer von Bongartz — Wed, 30 Oct 2002 07:59:03 GMT

There is absolutely no need to shut down the host.

You should do the following:

1) Connect the host

2) Wait for Raid System to go to state READY

3) Plug one old disk; replace with new one and wait for rebuild to finish

4) Plug the second disk and replace the same way

Regards
Rainer

Re: AutoRAID

U.SivaKumar_2 — Wed, 30 Oct 2002 08:05:56 GMT

Hi,
Iam aware that disks can be changed with host online.

But What I want to know is that Can I replace the other hard disk with the situation decribed
i.e BALANCED.

regards,
U.SivaKumar

Re: AutoRAID

U.SivaKumar_2 — Wed, 30 Oct 2002 08:10:45 GMT

But Array shows BALANCING ONLY when the host is down . When the host is up the Array shows
READY. So how to go about now ?

regards,
U.SivaKumar

Re: AutoRAID

Vincent Farrugia — Wed, 30 Oct 2002 08:14:05 GMT

Hello,

No, you can ONLY replace the harddisks ONE AT A TIME. When the array shows "balancing", it is still in a caution state, ie. not RAIDed. Wait until the rebuild complete, THEN and only THEN replace the next harddisk.

HTH,
Vince

Re: AutoRAID

Vincent Farrugia — Wed, 30 Oct 2002 08:36:46 GMT

Hello (again),

Ok I did some research...

Balancing is the process of automatically spreading data equally across all disks to increase performance. It has nothing to do with rebuilding. When a fixed amount of data is written or read from multiple disks, the throughput of the process increases greatly.

So you are safe to replace another disk if you are in a "ready" state when online, yes.

HTH,
Vince

Re: AutoRAID

Insu Kim — Wed, 30 Oct 2002 11:37:59 GMT

This is what "Balance" is doing in the AutoRAID.
When a new drive is plugged online, current data is automatically balanced across all the disk drives including the newly added disk for maximum performance.
It typically takes a lot of times to balance data across all disks.
While balance is running, you can replace a disk drive but HP recommends that you wait until balance is complete.