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How to add a drive and convert from RAID-0 to RAID-1?

fixitjr
fixitjr asked
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Last Modified: 2012-08-14

I have a Dell PowerEdge 1750 server with built-in PERC SCSI RAID controller.  I recently upgraded from a pair of 18GB RAID-1 drives to a single 72GB drive RAID-0.  I now have a second 72GB drive and want to install this into the server and mirror it to the first drive.... Simple enough, right?

Well, I installed the second drive, ran the BIOS RAID Management utility and was able to delete the existing RAID-0 Array Configuration and set up the pair in RAID-1.  Except that it wouldn't boot.  Nothing happened after the post - no error messages, just one brief flash of the drive lights and then nothing but a blank screen.  I changed back to RAID-0 config and it booted OK.  Then I made the change again and started to run the 'Check Data Consistency' util, but I was a bit pressed for time with having my server down that long and so I cancelled that after two or three minutes 'cause it looked like it was going to take two hours and I didn't think it was going to help anyway.  Then I rebooted again and it actually got to the "Loading Windows" (Server 2003) screen and stopped....

I went back to my original configuration and brought the server up, but now I'm thinking that I'm going to have to run the Consistency Check after re-defining the Array.  

Has anyone else done this before?  If I have to bring my mail server down for 2 ~ 3 hours then I'll schedule it and do it after hours some day, but I'd really like to verify that it'll fix the problem before I get into it.  I originally thought that the controller would automatically see the drives as out-of-sync and do the mirroring on the fly, or at least let me tell it to re-build the Array manually but it didn't seem to do it automatically and it doesn't detect a failed drive and so won't give me the option to re-build.

My other thought was to define the new RAID-1 Array with the second drive installed, and then remove it before starting up the server to force the controller to think the second drive had failed and allow a manual re-build, but it just shouldn't be that complicated....

Any help is appreciated.

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Commented:
Can you post teh exact controller model? It may be a siple matter to cheat the RAID controller into building you a mirror.

BTW - RAID 0 is a striped RAID type with no redundancy. It sounds like your using it as a synonym for a single disc?
Commented:
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no it will not fix the problem, the best thing i would suggest is to take an image of the existing working config (i.e., Raid 0 Config with 72GB Single)  then clear the raid configuration, create new  Raid 1 configuration and restore the image to the Raid 1 new configuration.

Commented:
why not just convert the existing single drive raid 0 to a raid 1?

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Commented:
"the "built in" controller on the 1750 is the perc 4/di
here is instructions on doing the conversion:

http://support.dell.com/support/topics/global.aspx/support/kb/en/document?dn=1078470&l=en&langid=1&c=us&cs=&s=gen

btw, no need to take down the system, just start the conversion when you know the system will be hit very little.
if you need further assistance or guidance, please post again!
jeff'"

I have accepted this answer, but I'm not sure those instructions will actually do what I need.  Adding a drive to an existing Array seems to be very different than changing the type of Array.

"no it will not fix the problem, the best thing i would suggest is to take an image of the existing working config (i.e., Raid 0 Config with 72GB Single)  then clear the raid configuration, create new  Raid 1 configuration and restore the image to the Raid 1 new configuration."

This is at least a 6 hour or so operation....  I'd /really/ rather not have to take this route.  Why do you say that the Consistency Check will not sort out the drives?  I can't account for the difference between no boot at all and the later boot-and-hang at the Loading Windows screen except to say that the couple of minutes I ran the check had actually synchronized the first couple of sectors of the drives.

"BTW - RAID 0 is a striped RAID type with no redundancy. It sounds like your using it as a synonym for a single disc?"

"why not just convert the existing single drive raid 0 to a raid 1?"

Yes, I'm using the terms synonomously.  RAID-0 is the only option the controller allows with only a single drive installed.  I just don't have the option to select RAID-1 with only one drive.





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Commented:

Sorry.  I will accept Jeff's answer, but I don't want to close the thread just yet.  Why can't I edit my posts?!?

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Commented:
>Why can't I edit my posts?!?
Only moderators and page editors (I think) can edit posts. If you need to add or change anything then you need to post again.

You get used to it... :-)

Commented:
look in the first picture on the link I sent, you will see a dropdown labled "virtual disk type" and a box containing the "available disks"...your virtual disk type will show raid0, you should have an available disk.  Click the available disk and press the "add disk" button, then change the dropdown to "raid 1" and press ok.

Author

Commented:

Well, I did it and I was able to make the change through the Array Manager Console in Windows.


Thanks to all, expecially tfjeff & meyersd!

A/.
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Commented:
Glad to of assistance!

Commented:
not a problem, pretty easy too ;)
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