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Adding drives to a power-edge 2900 w/perc 5/i RAID controller

I have a server that is getting low on drive space.  It's a Poweredge 2900 set in a RAID 5 with three 80 gig hard drives.  A Perc 5/i is controlling the array.  I have multiple new 80 gig hard drives and would like to either add onto the array or create a new RAID 5 array to act as storage only.  What would be the best way to do this?  Ideally i do not want to have to rebuild the existing array because of time restraints and the fact that i could lose data but i am open to suggestions.  If i can add disks and create a new array and just use these for network shares that would be idea.  
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You can create a new array using the new drives without disrupting your existing RAID5 set.  Depending on your OS, you should be able to do this with the dell-provided OpenManage software that came with your server while the server is running.  If you don't have it, it's available for download at:

If you prefer, you can also boot up the server and press <CTRL><R> to enter the PERC 5 BIOS, where you can accomplish the same thing.

You said you prefer to create a new array, but in case you were wondering, it IS possible to expand your existing RAID5 set while the server is live and running.  You can expand the array one disk at a time, so you'll need to add a drive to the array (I believe the option is called "Expand" or "Extend"), wait for the RAID array to finish rebuilding, then add the next drive, and so on.  IIUC, There's always a small risk of data loss during this process while the array is expanding to use the new drive.  The risk comes from one of the existing disks in your array failing before the expansion is complete.  The risk is small, but keep in mind that disks usually fail when under intensive use - and array rebuilds and reconfigurations definitely qualify as intensive use.
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Just a small correction to slam's otherwise perfect post:

You cannot rebuild a drive at a time to make your array bigger.  Once the drives have all rebuilt, the array will still be the same size, and the only option you will have at that point is to create a second array across that set of disks using that additional space.  This will be just like adding drives in an additional RAID array (in that you will have a new separate "disk" and drive letter in Windows, but it can be less stable having multiple arrays across the disks.

The only way to make an array bigger is to ADD drives to the array.  For example, you can convert your 3-disk RAID 5 to a RAID 5 containing as many disks as your 2900 will hold.  This is called a Reconfigure and is done in the OpenManage Server Administrator software ... Storage, PERC, Virtual Disks, Reconfigure from the dropdown menu of available tasks for your RAID 5 Virtual Disk.

The PERC does not support automatic or manual expansion of the array after replacing the disks with larger ones.  You might hear or see a trick called a Retag to remap the array to fill the capacity of the disks, but this is a side-affect and is not what the Retag is for.  This will cause instability in your array and puts your data at risk, so don't be tempted by this seemingly attractive option.
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I was hoping you'd pop up here.  So would you suggest a new array with these new disks instead of trying to "add disks to an existing array"?  Will you provide me the steps in making this as painless as possible?
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PowerEdgeTech nailed the correct terminology for the idea I was trying to convey.  :-)  I knew I might be getting the exact nomenclature wrong, but  you've now got two posters confirming that you CAN indeed nondestructively make your existing array larger by adding your new disks to it.  I've done it before and knew it was possible - it looks like I was mistaken about having to add the drives one at a time, though.

If I'm understanding PowerEdgeTech correctly, once the disks are inserted and recognized by the PERC as available space waiting to be configured, you can use Reconfigure to add as many of the available disks as you like to your existing RAID5, and once you pull the trigger, the PERC will expand your 3-disk RAID5 set to a 4, 5, 6, or more-disk RAID5 set -- depending on how many drives you choose to add -- and do it all in one shot.

Keep in mind that once the reconfigure is complete and your "Disk" now appears larger to the OS, your partition size will not yet have changed.  If the volume you're wanting to increase in size is not a system volume but a data volume, (and assuming it's a Microsoft server OS Win2k or newer) you should be able to use the Diskpart.exe command line utility to extend the volume while windows is running:   If it IS the system volume, you could try running diskpart from the recovery console or a boot disk, but I don't honestly remember whether diskpart will be able to extend the system volume even from the recovery console.  It may work, or it may refuse - some quick searches didn't turn up an immediate answer but you should be able to determine this without too much trouble.

What I'd probably do is download and burn a GParted Live CD ( and see if it recognizes the array being presented by the PERC as a disk it can work with.  If it recognizes your existing partition, you can use this excellent tool to non-destructively resize the volume to use the newly available space.  It's generally very safe, but as always, be sure you have a backup of any data you care about in case the worst happens. :-)

As for the repartioning your server information above (if you go the Reconfigure route):

Diskpart cannot extend system partitions.  Dell's ExtPart can (as well as a handful of other application), but note that in order to simply extend a partition, you must first delete the adjacent partition as it can only be extended into Unpartitioned Space.

There are other utilities (usually costing $$$) that can resize while keeping all data intact (like Acronis Disk Director).

Not sure if I understood your last comment, but just to clarify:  GParted will not be able to do anything with the RAID array (as far as expanding the actual array/virtual disk) - this is simply not something that any partitioning tool can do.  You can use it to extend "partitions" like C:, but again, you must first delete the adjacent partition before you can extend C:.
To clarify my comments about GParted:

GParted is a partition editor, like Acronis Disk Director, PartitionMagic (Formerly by PowerQuest, now by Symantec unless it's changed again), and many others, but GParted is based on free and open-source linux tools, and is therefore a no-cost utility.  GParted is not a RAID tool and does not attempt to modify a RAID array itself in any way.  The PERC controller *should* present the RAID array as a single logical/virtual disk that "looks" like a single hard disk drive to most utilities and operating environments.  

The reason I said "...if it recognizes the array," is because on one occasion, I had an Acronis product incorrectly represent a RAID1 mirror configuration as two physical drives, rather than 1 logical drive.  It was on an HP server, and I've never seen that happen on a DELL server using a PERC controller.  I don't know if the cause was the fault of the RAID controller or Acronis, but regardless, the utility "saw" two drives instead of the single drive it was meant to "see". I don't expect GParted to have trouble recognizing the array as a single logical drive and thus being able to work with the partitions on it -- in fact, I think I've used GParted on a PERC RAID5 array before, though I can't swear to it -- but in the off-chance it doesn't correctly see the single disk presented by the PERC, there are other options to explore.

Techit2, if your current RAID5 array is being used as a "C:" partition for your Windows operating system, and you follow PowerEdgeTech's excellent instructions to add your new drives to that array and "Reconfigure" it to make it larger, here's what I would expect to see:

Before you make any changes, if you use Disk Management to look at the Disk (probably Disk 0), you will see that if your OS is Server 2003 or older, the C: partition fills the entire disk.  (If your OS is Server 2008 or 2008 R2, you will see one or two smaller partitions beflore the C partition, but the C: partition will still likely extend to the end of the disk.)  After you've added your new disks to the array and the reconfigure is complete, disk management will show the C: partition only occupying part of the available space, with unpartitioned space now showing at the end.  

PowerEdgeTech is correct to say that if there were a partition adjacent (i.e. "after") the C: partition, you would have to delete it before you could increase the size of the C: partition.  However, in this case, as you would have just added free space to your array and effectively made your Virtual Disk look bigger to the OS, there would be no partition after C:, assuming C: was the last (or only) partition on the virtual disk.  (If you also had a data partition on the disk -- say, a D: drive that appeared after the C: drive in Disk Management -- the free space would appear after the D: drive. In that case, you'd have to do something about the D: partition (resize it or delete it) to make space available immediately after C: so you could extend the partition into the free space directly after it.)

Power edge tech,

I have installed the open manage software and it is showing that my firmware, drivers, storeport is out of date.  Should i update all of these before adding drives?
If you were doing a Reconfigure, I would say yes.  The updated firmware and drivers have fixes that can make your server more stable, so I would plan on doing it soon, but not upgrading to add a new array will not affect anything.
OK so I'm attempting to add disks and they are "ready" but "new create" is not an option from the drop down.  Do i just choose clear?
No, Clear is for foreign configurations.  Since they are showing Ready, there is nothing to clear.

Create/New is not a function of a physical disk (which is where your screenshot is), it is a function of the RAID controller, so since they are showing Ready:
"Go to Storage, PERC, Information/Configuration (link at top of page), and select New/Create from the dropdown menu."
Ok sorry about that.  Please confirm that i am going to "create virtual"  I do not see create new.
Yes, Create Virtual Disk is what you want.  I just could remember if it said "new" or "create" :)
Sorry ... I just could not remember if it said "new" or "create" ;)
OK so I've added 5 (80) GB drives and chose RAID 5 the next screen is saying the max size is 148 GB?  It's seems to be adding only three drives and then asking if i want to make the other two hot spares?  Sorry for the step by step requests but this is my first time doing this.
That's ok ... I'm not sure why it would want to set two of them as HS's unless there is a box checked somewhere on one of the screens to configure a hot spare.  You might try the Advanced Wizard.  I'm not in front of one right now to see where it might be asking for HS.  Are any of the drives configured as HS's in Storage, PERC, Connector/Enclosure, Physical Drives?
I sorry i had to attend to a pressing need.  I found in the advanced setting where to pick all 5 disks and i have done that.  In windows it's showing as unallocated drive space.  Do i convert or initialize to MBR?
Good.  You should be able to simply Initialize it, then format it.  There's no need to convert the disk to anything else.
Sorry ... MBR is fine ... GPT isn't necessary on this small of storage area.
I have initialized it and now it's asking to pick between a extended or primary partition under a right click on the drive space after initializing it.
Primary.  On an MBR disk, you can have up to four Primary partitions.  If you need more partitions than that, you must have 3 Primary partitions and one Extended partition.  Extended partitions allow you to create "Logical" drives that act like regular partitions.
Excellent walk through.  This worked out great.
Good .... glad to hear it :)