Adding Additional Disks to a RAID 5 Array

[Chris Stradling]

Hi,

This may sound stupid, but here goes.

I have a ML350 with 532 smart array controller, RAID 5 setup as follows:

Logical Drive 1 (138919MB, RAID 5)

Physical : 3 x 72.8GB drives

I have 3 new 72.8 drives that I want to add to the array, is it just a case of putting the drives in, and the controller builds them in to increase the size of the logical drive? or do I need to do something else before the drives go in.??

Any help here, much appreciated

[Steven Clementi]

Chris:

There are a few steps to the process...

Step 1. Add the drives

Step 2. Using ACU, expand the array by adding the 3 new drives to it.

Step 3. Create new logical drives or extend existing logical drives or do both

Step 4. Extend partitions within the OS where necessary.

The process is not automatic.


Getting past step 4 is usually the biggest hurdle. Steps 1 through 3 are the the easiest, but usually the longest.

What OS do you have?

Do you have 1 logical drive? or multiple logical drives?

Is your intention to extend logical drives? or create new ones?


Steven

[Ryan Goff]

Update all firmware by running the firmware maintenance CD:
http://h18007.www1.hp.com/support/files/server/us/download/23331.html

Which operating system are you using? You can do this while online in the OS but there are different instructions for Novell and Microsoft.

Make sure you have a known good backup.

It wouldnt hurt to get a copy of the array diagnostics report to make sure there are no errors on any drives before proceeding as you do not want to run into any trouble during the expansion.

This is also a long procedure, takes 20-40 minutes per GB.

[Chris Stradling]

Hi Steven,

Thanks for that.

It is Windows 2003 Server.
1 Logical Drive.

There are 3 partitions. 1 of which i want to increase using the new disks.

Chris

[Steven Clementi]

Chris:


You have 2 options here. You still need to add the drives to the array so that does not change. The problem you have is... you will need some 3rd party utility to change your partition sizes as you will not be able to use diskpart.

Your second option would be to add the drives and create a new larger logical drive, copy over the data you wanted to expand, change drive letters and you should be good. This would obviously leave an unused potion of your original logical disk, but perhaps you can find another use for it, or get that 3rd party utility and get rid of it.. and increase the sizes of the two other partitions.



Steven

[Chris Stradling]

Hi Steven,

I have just been reading a microsoft white paper, that says diskpart.exe can be used to extend a basic partition in server 2003 (this option was not available in server 2000) The partition I am looking at extending is a data partition only, not system. Can you still see a problem with this? Is it that all 3 partitions are part of the 1 logical drive that it will not work?

Thanks

Chris

[Steven Clementi]

Yes, since the partition is on the same logical drive as the os/system partition, it can not be done with diskpart.

While the process is generally non-disruptive, the disk does have to go offline momentarily, even if just for a split second, which could cause the system to Blue Screen (if you did that to the drive with the system partition on it.


As for extending a basic partition in Windows 2000... I have dones this many time with no issue. Not sure why/where is says it is not possible.


Steven

[Chris Stradling]

Ok thanks.

I will look at purchasing a 3rd party app. and go with your first recommendation.

I have used Partition magic for personal use, would you recommend this or something else for use with HP hardware?

Thanks

Chris

[Prashant (I am Back)]

check the Doc

It will explain i think so