I have a Dell PowerEdge with a RAID 5 array of 3 disks, and I want to add a fourth disk to it to expand the capacity of the volume.

I don't want to reinitialize the whole RAID 5, because I want to keep all the data on it and just expand it.

Can I do this with OpenManage while Windows is live, or do I have to do this on the boot menu while the OS is not mounted?

Here is a screenshot on OpenManage Server Administrator:

Physical Disks on Controller PERC 4e/Di

And also please tell me how to achieve this. Thanks!

2 Answers 2


I found the solution by myself, and here is how to achieve this WITHOUT data loss:

With the disk inserted, go to OMSA (OpenManage) > Storage > PERC > Enclosure/Backplane > Physical Disks, and make sure your disk is showing 'Ready'. If you don't see the disk, you may need to reboot for the disk to be detected in OMSA.

If the new disk's status is 'Foreign', go to OMSA > Storage > PERC > Information/Configuration (link at top of page). Choose 'Foreign/Clear' from the dropdown menu. Then disk should enter a 'Ready' state.

If the new disk's status is 'Ready', go to OMSA (OpenMange) > Storage > PERC > Virtual Disks. Choose 'Reconfigure' from the dropdown menu for your RAID 5, follow the wizard to add the physical disk to the array.

Virtual Disk Reconfigure Option

Source: http://en.community.dell.com/support-forums/servers/f/906/t/19378577.aspx

  • ...and now you should accept your own answer. BTW - this works with every OMSA. Also with linux-based systems.
    – Nils
    Dec 6, 2011 at 21:13
  • 1
    This does NOT do the 'whole trick.' This still required a 'reboot' AFTER you finish the reconfigure. I tried 'rescan' via OMSA and 'recan' via Diskpart, and Disk Management will NOT see the new, Unallocated space, UNTIL you reboot - unless someone knows a trick that I don't know.
    – user156657
    Jan 29, 2013 at 21:20

I was able to perform the same process adding two new drives with a Perc H310 controller on an exsisting Raid 5 configuration. I did notice that when I began to run through the Reconfigure task in the Virtual Disk settings, it defaulted to "Raid 0" - watch out. I had to manually select Raid 5 to ensure that the drives showed up properly as unallocated space in Windows. Additionally, I required absolutely no reboot through the entire upgrade process, from hardware installation to extending the volume in Windows.

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