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jmac44Flag for United States of America

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Add two additional hard drives to raid 5 array

I need to add two additional hard drives to an already configure raid 5 array. the machine is a dell pe2850 with perc 4e/di raid controller. I tryed to install dell Open manage server adminstrator where I'm told it's a snap to use and complete this task but the applicataion crashes on install. so I'm left with the embedded perc 4e/di and I am not comfortable enough to use it with out help.
When I go to configure/add drives the only option I get is set them up as raid-0 or raid-1. Is there anyone in here that has experience with perc 4e/di configuration menu that can help me? My bigest concern is not wanted wipe the data from the 3 previously configure raid 5 disks. My objective is to add the additional disk to the array for expanded disk space to the OS.
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PowerEdgeTech
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In CTRL-M, you want to choose Reconstruct from the main menu to add drives to your existing RAID level ... it will reconfigure your 3-disk RAID 5 to a 5-disk RAID 5.

What kind of error are you getting when installing OMSA?  What OS and SP do you have?  What version of OSMA did you try to install?
1) Take a good backup
2) Add new disks
3) Delete the array and recreate it including the new disks
4) Restore the data from backup.

I suggest you better fix OMSA.  If you are not able to update the OMSA with latest version try uninstalling it and install with latest one .  If you are getting any error while uninstalling let me know I'll help you out.
suj ... that is surely an option, but the easier functionality to add disks to the existing array is built-in to the controller and is accessible through OMSA.
First, devil's advocate ... if you don't want to risk losing your data then this is EXACTLY the right time to do a backup.  Since you effectively have 2 disks of usable data, and 2 scratch disks that you want to add, then why not kill 2 birds with one stone?

Build a 2-disk RAID0 with the 2 scratch drives, while leaving the 3-disk RAID5 alone.  Then use whatever backup software you have (or download an eval of something), and back up the RAID5 and restore it to the RAID0.   Usable size should be the same.  If it works, and you can boot off of the RAID0, then you know you have something that can actually get you going in a disaster, without risking your RAID5.

Then, of course, do another backup to perhaps a large SATA drive that you connect to an internal SATA port (or eSATA or even USB or network iSCSI, whatever you can do) .. and then blow away the RAID5 and build it with the correct number of disks.

Here is a link to details on how to get the R5 expansion to work, straight from Dell.  However, best practice before doing a RAID migration is to have a full backup.  If you take a power hit or drive fails in the process, then it is likely you will suffer some data loss.

Is your data worth the extra time and inconvenience of a full backup? Your decision.
http://en.community.dell.com/support-forums/servers/f/906/p/19422969/19995700.aspx
"best practice before doing a RAID migration is to have a full backup"

Of course, but a backup/restore is not the only option for moving to a 5-disk RAID 5 ... and it wasn't his question.
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>If you take a power hit or drive fails in the process, then it is likely you will suffer some data loss.

Not according to the Dell documentation.
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ASKER

These are good suggestions and I appreciate your responses. A Dell tech helped me build the raid5 4 years ago and I do remember him saying that adding additional disk(s) could be done without distroying the original 3 disk set. Unfortunately I know longer have the Dell support contract on this mahine - reason for posting it here.

The machine is running Win2k8 Std. SP1, Exchange 2010 SP1 RU2. I do a full backup nightly using Windows Server Backup but just discovered through this endevour that I cannot do a full restore without having Exchange 2010 SP2. That said I have rebuilt the email server on another machine and restored the database to it.

The OMSA was downloaded from Dell's website. I have an account login with all my machines list via service tag. I'm certain it is the latest version. When I try to install it the error message box is "can not find e:/" I do not have a local E: drive on the machine but do have a network e: drive. I suspect I may need to log on as the local admin and not the network admin and try again. Does this sound like a reasonable approach?
you can do a whole backup a variety of ways that has nothing to do with windows using the existing hardware, as long as you have an hour or so depending on # of GB of disk).

1A. If you want to actually do a D/R test to make sure you can restore to replacement disks or another computer in case of problem do this step ....

Go to the BIOS of the controller and tell it to create a RAID1 using the 2 free disks (Or attach an external drive if you just want to make a backup and don't want to test that you can restore using the controller, whatever you prefer).  

1B.  If you just want to backup and get this over with ... plug in a scratch drive (NOT TO THE RAID, but internal SATA, or eSATA, or even a USB-attach (but that will be slower) ...

2. Go to ubuntu.com 's live USB distribution so you can make a bootable USB stick for the desktop version.  Obviously use a different PC for that.  (All data on the USB will be lost.  If you prefer you can make a bootable DVD or CDROM).

3. Plug in the bootable device, set the BIOS to boot to it.  From there you run disk cloning software, choose target & destination, and partitioning and make copy.

Here is nice article that walks you through cloning and doing all of this
http://www.addictivetips.com/windows-tips/create-disk-image-clone-hard-disk-partition-with-ubuntu-live-usb/

4. Once you clone then you can either just unplug the HDDs or controller and make sure you can boot, and then play with it if you want, I recommend re-cloning after you do a boot test as windows makes changes whenever you boot to different device, so I would rather have a clean copy.

5. Then now you have tested a backup, and have one, just blow away the RAID5, build a new one with all the disks. Then you don't have to worry about needing OSMA, as that can be done from the BIOS.  (Obviously locate the options on the BIOS to do this first, and make sure you can find how to build a new array).

6. Then take the backup you made and restore it.  You can resize partition in the process.
If you are in the States or Canada, support is free regardless of warranty status.

Sounds reasonable to try, although you don't usually need a local admin to install it as long as your network login is in the local administrators group (or by default, like Domain Admin).

Make sure you are using this version:
http://ftp.dell.com/sysman/OM-SrvAdmin-Dell-Web-WIN-6.5.0-2247_A01.10.exe

Download and run it to extract the files, then run C:\Openmanage\windows\setup.exe.  Choose Custom and leave everything as default, but make sure that Storage Management is installed.  You can extract the files to a drive other than C: to run the install from, but you cannot actually install OMSA on any partition but C:.
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ASKER

Power, thanks that is the version I have. I installed as local admin and made sure Storage management is installed. The only options under Physical Disk Properties on Controller are:
Blink
Unblink
Assign Global Hot Spare
Prepare to Remove

Do I Assign Global Hot Spare? Will that add the diask to the array?

Dlethe, I appreciate the info and may use one of your suggestions but first I want to make sure but there is not an easier way to add additional disks to the array.
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PowerEdgeTech
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ASKER

The drives are reconstructing. I'm sure this will take some time but it appears to be the solution I was looking for.
Good luck and take care.