Friday, August 25, 2006

After-OS RAID install on a Dell PowerEdge 2800

Task: A Dell PowerEdge 2800 server with Windows Server 2003 was to have its one physical hard disk drive (HDD) upgraded to a multi-disk hardware RAID system.

I want to use a disk cloning system (like Norton Ghost) to transfer an exact copy of the standalone HDD to the new RAID disk system. This poses two problems:
  1. The system would not boot, because the SCSI driver of the RAID controller was not installed in the kernel of the OS. After the clone, you could of course run the Windows 2003 setup CD and install the SCSI driver from a floppy disk, but it has to be a physical floppy - if you don't have that or even a floppy drive, you're stuck. Personnally, I chose another approach that I find more convenient (see below).
  2. On the PowerEdge 2800, the Raid controller is a chip that, when installed, actually takes over the control of the physical disk bays of the computer. This means that no clone can be made because the standalone HDD and the RAID volume can not coexist on the server.
Needed: (You could probably do this with other tools as well, but this is what I had available)
  • A Ghost network boot disk (CD or floppy) for your server
  • A spare server
  • A Ghost network boot disk (CD or floppy) for your spare server
  • A LAN with a working DHCP server
  • A driver for the SCSI RAID controller (not necessarily on a floppy)
Successful procedure:
  1. Still running the OS from the original HDD (that is to be the source for the RAID disk), the SCSI driver for the RAID controller were installed. On Server 2003 it will ask you to install the device first (on the good old NT4 Servers, this was easier to accomplish). On my server however (a Dell PowerEdge 2800), there are two on-board SCSI controllers, whereof only one were in use, making the following possible:
    1. Open the unused controller from the Device Manager and choose Update Driver (be very sure you have chosen the unused one - otherwise you may not be able to boot again)
    2. Click Have disk and uncheck the option to only show compatible drivers. Locate the RAID controller's driver and select it to replace the original SCSI driver for this unused controller. This will of course render this unused SCSI controller useless for now, but it installs the driver into the OS so that the RAID controller later will be recognized and handled in boot.
  2. Install the physical parts into the computer - including the RAID controller (chip) and the disks it will control
  3. Set up the RAID volume on the RAID controller. This is done during boot. The controller tells you to push a function key to access RAID controller options/setup.
  4. You must also enter the server's CMOS setup and set the RAID controller as the boot device.
  5. On most systems you can now boot from a Ghost boot disk and image the old HDD to the new RAID volume. As mentioned, this does not work on the PowerEdge. As a workaround, a spare server was used. The old HDD was installed there. Now the following steps were taken:
    1. The now RAIDed server was booted with a Ghost network boot floppy, selecting TCP/IP and Slave from the Ghost menu. Make a note of the DHCP given IP address. If this goes wrong, check that you have a DHCP server running.
    2. The spare server was then (afterward - important) booted with a Ghost network boot floppy, selecting TCP/IP and Master from the Ghost menu
    3. The IP of the RAIDed server is given as the Ghost slave to control
    4. The RAIDed computer is ghosted over the net, and will, because of the previously installed RAID controller SCSI driver, boot nicely when finished.

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