Skip to main content
Start a Conversation

Unsolved

This post is more than 5 years old

PCFriendly

4 Posts

17047

June 24th, 2006 19:00

PowerEdge 2850 Perc 4e controller - How to go from Raid 1 to Raid 5 without data loss?

I have been scanning Dell's website for hours and maybe I'm just lame but I swear I can't find the instructions to migrate from a Raid 1 to a Raid 5 array. I bought two new drives and they are "ready", but I am terrified (like many others) to change my configuration. Is there a specific instruction set to do this? I "temporarily" changed the array configuration and thought I wiped out all my data but was able to simply to change it back.
 
One of the Dell tech's told me I could do this so I was really excited considering I thought I was going to have to backup/wipe, create array, reinstall, rebuild server. I've been scanning through this forum for several hours now trying to find someone else who has done this to no avail. Can someone point me in the right direction?
 
Thx!

PCFriendly

4 Posts

June 24th, 2006 19:00

Nevermind...I finally found the link!

PCFriendly

4 Posts

June 24th, 2006 20:00

I guess I spoke too soon. It won't let me "reconstruct" to Raid 5. I can only choose Raid 1 or Raid 0. Can someone tell me what I am doing wrong?

pcmeiners

6 Operator

 • 

1.8K Posts

June 25th, 2006 14:00

From the LSI site....
 
Migration or expansion is possible for any of the following:
- 1 drive RAID 0 to a 2 drive RAID 1
- 2 drive RAID 1 to a 3 drive RAID 5
- n drive RAID 0 to a n+1 drive RAID 0
- n drive RAID 5 to a n+1 drive RAID 5
- RAID 5 to RAID 0
- RAID 1 to RAID 0
You cannot migrate to a RAID level that reduces the drive count or reduces the data area.
 
How many drives are in the server excluding the new drives ? You need a two drive raid 1, and a drive with the same EXACT or greater capacity to migrate to raid 5..the new drives must have at least the same capacity, a drive even 1/10 gig smaller will not do.
 
I have never added 2 new drives in a raid 1 to raid 5 expansion,  not sure if you can do this. You may need to add 1 new drive, create the raid 5, then add the second new drive, which will not be added to the original volume unless you use third party software to expand the volume. In some instances MS Dispart.exe will work, if not Acronis will work.
 
 

PCFriendly

4 Posts

June 26th, 2006 01:00

I have two 300 GB drives installed (mirrored Raid 1). I added two new 300 GB drives (identical to original drives).

I don't have the Windows Dell Array manager installed. I tried to use the manager at bootup to upgrade the array.

I assumed that I should be able to since Raid 5 only needs 3 drives. I was going to upgrade to a Raid 5 array using three

of the drives and then convert the 4th to a Hot spare. Am I only able to do this through the windows based Array manager?

Heck, back when I was doing Array stuff not too long ago, The idea of even upgrading an array other than adding a drive to a

Raid 5 wasn't possible. I'm thrilled with the idea of being able to avoid the headache of having to wipe/build array/load and restore.

pcmeiners

6 Operator

 • 

1.8K Posts

June 26th, 2006 13:00

I use the bios setup to convert raid arrays. I would also recommend the drive firmware be the same, Seagate will give you access to firmware revisions if you call them. I would try the conversion with 3 drives, then add the 4th as a hotspare. Expect the conversion to take hours, as the parity is considerable on such large drives.
With large drives, once you create the raid 5, I would run scheduled consistency checks bi monthly if possible, even with a hotspare, as the chance of getting multiple block errors (doom)  within a short period of time increases with larger drives. Dell has not caught up, Lsilogic recommends more than once a month if possible.
 
 
LSIlogic makes the perc4, 4E, di
Since it been a while since I did a raid conversion I called Lsilogic, this is their recommendation....
Download the power console plus software from the site
 
Install it, highlight each disk make sure there are no errors on the disks, run consistency check if there is.
 
You can drag and drop the new disk onto the raid 1 array, it will automatically ask if you want to convert the array to raid 5
 

Message Edited by pcmeiners on 06-26-200610:01 AM

Was this post helpful?

View All

No Events found!

Top