Adding a Drive to a RAID Array 3

[mugs82]

Hello All,

I have a compaq proliant dl380 with a Smart Array 5300 controller. We implemented RAID 5 with three, 36GB drives and are now running out of space. I would like to add a 4th drive to the array and purchased the a 36GB drive from Compaq and increase the size of the data partions. This server is a member server in an NT 4.0 domain and used as a file server and runs our backup software.

I do not have a lot of confidence in our current backup system and it works very eratically. I have read that when adding disks to an array, the best practice is to format the drives and rebuild the array then reload the files from a backup. This scares me.

I am considering ghosting all of the partitions, formating the drives, the rebuilding the array with the 4th disk included. Has anybody done this? I could use some guidance...

 

[victorv]

hi,
what you have read is almost true: exist few raid controllers that permit you to add a disk dynamically in an array already built.

About ghosting, take in mind the following:

1) the cloning product manage your OS ( NT4Srv, W2K Srv ?)
2) With the system ghosted on a CD(s), is the program
able to manage the RAID controller ? (Driver ? )

I belive the best is to reinstall, but I understand
it is not easy.

A workaround solution can be to put the 4th disk not
in the RAID, and save on it all not critical data (always
backed-UP by backup program). Or if you have space (and
money) buy 3 new disks and move all user-data on the new
volume managed by the same controller. The user will see
their data always under a share (whit the same name) also
if they will be in the disk E: and not in C: .

bye

 

[lifto]

I have a similar set up to yours (DL380, 4 36gb HD's in a RAID 5). In my case, I trust my backups but when I need to be absolutely certain of the integrety I do a full back up and then copy EVERYTHING to another hard drive. Now days you can get a 100gb HD for about $100. Get one and put it in another machine and copy everything from the raid to the HD. Put the new drive into the DL380 and re-build you RAID and then use the data from your back-up or the 100GB drive to restore the data.

I don't think I would trust an image unless I tested it BEFORE I zapped my RAID. I have been surprised a couple of time with what I thought were good images only to discover they were corrupt.

HTH

 

[jaeddy]

I am somewhat surprised that Compaq's tools do not allow you to add a drive to an existing array (I'm assuming this is a hardware array since you mentioned the 5300). Have you installed the array manager from Compaq?

 

[mugs82]

Yes - I have the Compaq Array Manager installed. I also figured that I could just plop in the new drive and use the CAM to add the drive to the array. However, you get a big warning that all of your data could be lost because Win2k doesn't support adding a disk to an array. I called Compaq and one of their techs said that was a standard warning. But I felt it would be wise to read up about it. That lead me to believe that rebuilding the array from scratch was the best option. Thanks for all of your comments. Anyone else?

 

[mugs82]

Just so you all know. I went ahead and added the drive and kept going inspite of the warning. It worked seemlessly. Although it took about 30 hours to complete the extension. The server stayed up and running the whole time.

 

[fitzdr]

Glad you went ahead with the drive add. I have done this several times with Compaq servers and Raid Arrays without any problems. I do find it irritating that W2K doesn't openly support dynamic adding of drives.

I don't have this problem on my Netware or Linux servers.