Converting Raid 0 Array to Raid 1 IBM Server

[OJEA]

I have an IBM server that has six drives of those six 4 are configured in a Raid 5 array and the other two should be configured in a RAID 1 array. As it happens when the arrays were being built one of the drives was hosed. I decided to build the RAID 5 array with 4 working drives and create a RAID 0 array with the one working drive with the intent of converting this array to RAID 1 once i'd received the replacement. I've tried using a number of the IBM server software products and thus far i've been unable to convert the array. Does anybody have any suggestions?

I've thought about killing the OS array with the OS drive removed but I'm not certain if i can rebuild the array while not formatting it.

I've also considered ghosting the OS rebuilding the array and then restoring the image.

I'm not terribly thrilled with either of these prospects and would appreciate some fresh ideas.

Thanks in advance.

 

[RMGBELGIUM]

Just think about it : raid0 = stripe , in case of a disk failure, you have no protection, so you loose your data.So converting a raid0 to raid1 is not possible,unless you are able to add an equal amount of disks to your controller, so you can make a RAID 0+1

rgds,

R.

 

[OJEA]

I think you may have missed out on some of the information provided above. I was waiting for the replacement drive to arrive so i'd have the second disk of equal size to build the array. I have it now and I'm not able to create the raid 1 array from the IBM Server Gui. Perhaps i've missed what you were trying to say but it doesn't seem like you've taken into account what i said.

 

[scsiraid]

Not enough information... It seems that you have created a 'single drive RAID0' and now want to add the replacement drive and convert this single drive RAID 0 to a 2 drive RAID 1.

What server? What RAID controller?

 

[OJEA]

It's using a IBM ServerRAID-5i controller card and it's a IBM E Server xSeries 335.

Let me know if i've missed anything else.

Thanks

 

[scsiraid]

Using ServeRAID Manager, go to physical device view. Click on the 'array' which is your single drive RAID 0. Right click and select Logical Drive Migration. Is migration to RAID 1 provided? Make sure your extra 'ready' drive is present. The case for single drive RAID 0 may not have been considered but I cant tell from here since my config is different.

 

[OJEA]

I'd previously tried that there is no option to convert the array to anything. I went through the contents of the help file trying both the 6.1 and 8.4 versions of the software. I don't believe the current configuration of the array will permit me to do this. I figured some sort of alternate approach that would enable me to recreate the array without formating the system drive.

Thanks

 

[ibmtech65]

YOU can not technically go from a 0 to a 1. But there is a way to do it and this is totally unsupported by IBM but we do it all the time. Meaning if for some reason you loose your data don't come crying to me.

Make a backup of your raid0 drive.

Start your raidmanager from within the OS. Delete the raid 0 so you have 2 ready drives.

Click create raid array and down at the bottom UNCHECK the initialize new logical drives. That way it does not wipe out the data on your raid0 drive.

Create a new raid array with your current raid0 drive and the other drive which are both ready since you deleted the raid0.

When you get to the screen where you apply the settings. STOP. pull out the new drive and leave in your former raid0 drive.

Then apply the settings. You will get a warning message just agree to it. Once the settings are applied your new raid 1 array will be critical.

Go to disk manager so it will initialize or find the new logical drive.

Verify your data.

Put the new drive back in and it will rebuild.

 

[OJEA]

Thanks I'll give it a shot and let you know how it turns out.

 

[OJEA]

ibmTech65,

I finally had a chance to carry out your suggestion. Everything worked out for me in the end so thanks. I'd change the suggestion you made a bit for any that are looking to do something similar. I found that when you tried to execute this inside the OS the commands were still run in real time rather post boot or what not. Basically deleting the array would have killed the OS. I did a test initially by simply making the drive defunct from within the OS to verify that the OS wouldn't be damaged while carrying this out. I'd use the IBM Server management disk to carry out Killing the array. What i did was I removed the OS drive and killed the array then reinserted the drive and carried out the rest of your instructions starting with creating the new array. Incidentally I'm not sure if this was just me being me but i wasn't able to get the server management 8.4 software to boot so i used the 6.1 that i found online.

Cheers

- J

 

[ibmtech65]

Yes, 8.4 is application only not bootable.