Converting RAID 1 to a RAID 5 without data loss 3

[packdragon]

I've been charged with the task of finding out what it would take to increase disk space using new hard drives. They're talking about converting a current RAID 1 (two 16GB drives) into a RAID 5 by adding a third disk. Is this a relatively easy task? I'm familiar with the basic RAID setups, but have never configured one myself much less converted one to another.

Another possibility was to remove one of the 16GB drives, have it mirror to a new 36GB drive, then remove the other 16 GB drive, install the other 36 GB drive and have it mirror to that then change the configureation somehow so that it would use the entire 36 GB of space and not just the original 16GB. Is this possible without reinstalling the OS?

I haven't looked inside the box in question myself, so I'm guessing it may be limited in the number of hard drives it can physically accomodate (it's a Dell Poweredge 1550). It has a Dell PERC 2/SC RAID Controller in it.

I wasn't sure which forum this belongs in, so I'm hoping it's ok I posted here since it is a Windows 2000 machine. I would love it if someone could point me in the right direction so I could get some comprehensive info on my options here...

 

[packdragon]

Small mistake on the RAID controller installed. It's actually a Dell PERC 3/DC & PERC 3DCL RAID controller.

- Zoe, that's ZOH-EEE, get it right please
- Just a little ol' MCP at Solien Technology
-

http://www.solien.com

 

[ErocEZE]

RAID technology uses a number of different techniques for storing data and maintaining data redundancy so changing RAID level requires first backing up the whole data and then you can define RAID level for a LUN again.

Hope this helps,

 

[packdragon]

Would the OS have to be reinstalled? Where can I find some How-To guides on RAID options and conversions?

 

[ErocEZE]

In response to

"Another possibility was to remove one of the 16GB drives, have it mirror to a new 36GB drive, then remove the other 16 GB drive, install the other 36 GB drive and have it mirror to that then change the configureation somehow so that it would use the entire 36 GB of space and not just the original 16GB. Is this possible without reinstalling the OS?"

This would not be possible as a rebuild(mirror) would build a partion with the size of 16GB(same as main drive) even on a 36GB drive. Unless you are not using the gigabyte boundry on the raid controller. Dont know how or if that feature is activited or de-activated by default, on that controller.

 

[ErocEZE]

Do you have access to Norton ghost, If so that would be a snap. Just make a image the current information and delelte and recreate the raid 5 array and then put the image back on.

Check here:

http://service1.symantec.com/SUPPOR...sf&view=docid&dtype=&prod=&ver=&osv=&osv_lvl=

 

[ErocEZE]

I have done a backup/clone of a windows2000 server with RAID even though it says it may not on that documentation.

http://service1.symantec.com/SUPPOR...sf&view=docid&dtype=&prod=&ver=&osv=&osv_lvl=

 

[dkediger]

A LOT depends on the controller - in general, not very many controllers support online RAID level changes.

If you break the mirror and remirror to a larger drive, you'll still have the additional step of expanding the partition.

Your quickest and most straightforward option might indeed be to reinstall.

Start with Dell Web/Tech support on the controller, look for online RAID level changes and see if anything pops up.

 

[vbrocks]

I think the best thing to do is set up two more drives and mirror those (preferably larger than 16gb)

 

[dkediger]

The Dell site also mentions this controller has two internal channels.

You can also just get three drives - a bit more expensive I know - and set up a separate RAID 5 array and move all your data there. As long as your case and power supply will support them.

 

[packdragon]

Thanks for the info guys, very helpful! Here are a few stars...

- Zoe, that's ZOH-EEE, get it right please
- Just a little ol' MCP at Solien Technology
-

http://www.solien.com

 

[vbrocks]

Thanks for the star... Let us know what you decide to do...

 

[packdragon]

It may be some time before the client makes a decision. I'm in the info-collecting stage right now. I did call Dell and found out that the machine has a maximum capacity of 3 internal hard drives, but I could attach an external RAID array to the second channel of the controller. That seems a simpler solution than trying to rearrange the guts.

- Zoe, that's ZOH-EEE, get it right please
- Just a little ol' MCP at Solien Technology
-

http://www.solien.com

 

[vbrocks]

I agree with you.....