CentOS based Firmware images with OM 7.2(PXE)

CentOS based Firmware images with OM 7.2(PXE)


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CentOS based Firmware images with OM 7.2(PXE)

NOTE: The solutions outlined below are NOT officially supported by Dell.

 A newer version of the firmware live image is available with OM 7.2 and this time with PXE images :). In response to multiple requests for PXE images on the linux-poweredge mailing list, I put together a rudimentary PXE solution for updating firmware. Let us go over the features of this version of the image first and then get to configuring the PXE solution.


The Hybrid ISO image is with OM 7.2 is posted at http://linux.dell.com/files/openmanage-contributions/om72-firmware-live/.



  • As in the 7.1 image posted at CentOS Firmware liveDVD with OM_7.1 this image only has the firmware updates and doesn't carry any OS Driver Packs.
  • The base OS in the image is updated to CentOS 6.3(64-bit).
  • The ISO image created is a hybrid image. Following the instructions listed in post Hybrid ISO images on Dell servers, this image can be used from an USB key as well
  • With the release of OM 7.2 the DTK packages raidcfg, syscfg and dtk-scripts are added to the image. More information on DTK packages is posted at Dell Openmanage Deployment Toolkit. Having the firmware updates and DTK packages in a single image, this image will serve as a single stop for users to configure everything on target systems before OS deployments.


NOTE: all the commands which need root privileges can be used with sudo on this image.



PXE Image Configuration


The PXE images can be downloaded from http://linux.dell.com/files/openmanage-contributions/om72-firmware-live/pxe


Kiwi is the image building tool, I have been using for building the live firmware images. In kiwi terminology, the PXE image I built is referred to as "RAM only image". If you are familiar with RAM only images in kiwi, please go ahead and configure your PXE servers.


In the RAM only configuration, the complete image is copied from the TFTP server to the system memory(ramdisk) and run from the memory. The OM 7.2 firmware PXE image is around 3.5GB, so the target systems will need at least 4G of memory for a smooth boot.


Before going any further let us define TFTPROOT. By default most of the distributions use /tftpboot directory as TFTPROOT. A request like 'tftp -c get images/xyz' should download the file TFTPROOT/images/xyz file on the tftp server (assuming is the tftp server). The files in the PXE images have to be copied to specific directories relative to the TFTPROOT, so wanted to define it properly.


Now, follow the below steps to configure the PXE image:

 NOTE: all references to below have to be replaced with your tftp server’s IP.


i) Create TFTPROOT/KIWI/config.default file on the tftp server. Populate the file with the following text




This line suggests that the image name Centos62-OM72-Firmware-Net.x86_64-1.1.0 downloaded from the tftp server has to be staged on /dev/ram1 (ramdisk). 1.1.0 is the version of the image and 32768 is the block size used during PXE transfer.


Please note different configuration files can be used for different target systems. Please refer to section 12 at kiwi doc for related details. For now, I will continue using the default configuration for all target servers.


ii) Copy the Centos63-OM72-Firmware-Net.x86_64-1.1.0 file to TFTPROOT/image/ directory on tftp server.


iii) Copy the Centos63-OM72-Firmware-Net.x86_64-1.1.0.md5 file to TFTPROOT/image directory on the tftp server.


iv) Finally kernel and initrd images have to be made available for the live firmware image to start boooting. In my setup, /tftpboot/linux-install directory has the pxelinux.0 file and /tftpboot/linux-install/pxelinux.cfg/default is my PXE boot menu configuration file. The kernel and initrd images are posted to /tftpboot/linux-install/kiwi directory and the corresponding PXE menu item is configured as shown below:


LABEL Firmware-Updates

MENU LABEL Firmware-Update

KERNEL kiwi/kernel.2.6.32-279.el6.x86_64

append initrd=kiwi/initrd-vmxboot-rhel-05.4.x86_64-2.1.2.gz  ramdisk_size=4500000  kiwiserver=





Screen shots of the PXE boot image:



After the kernel and initrd images are loaded to memory, the root image is downloaded from the tftp server. The progress of the same is show above.

After the root image is copied to /dev/ram1, the md5sum of the image is compared to that listed in Centos63-OM72-Firmware-Net.x86_64-1.1.0.md5 on the tftp server. After the md5sum is verified, the server continues to boot.




If you haven't used any of the Firmware liveDVD images before, you can follow the instructions listed at CentOS base liveDVD to update firmware on Dell servers to update the firmware on the target systems.




Issues to watch out for:

  1. If the target system has multiple Network interfaces, the PXE boot image attempts to bring up all the interfaces. This might add a few more seconds/mins to the boot process.
  2. The boot images is 64-bit, so the legacy systems with 32-bit procs will not work with this image.
  3. This image only carries the network drivers part of the CentOS 6.3 release. If any of your NICs need custom drivers, this image will not work directly.




We would very much like to hear from everyone using these images. Please leave us a note on poweredge mailing list or a comment below on how you are using these images and what changes you would like to see in these images. 

P.S: the root password is "linux" on the live images.

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  • We noticed that the PXE image fails to update the BIOS and IDRAC firmware. This is because the usb-storage module is blocked from autoload and this is causing the update failure. I replaced the image at the above mentioned links with the fix. Please update your PXE environments with the new image.

    Thank you


  • I ran CentOS Live Image 7.4 OM74 on 13G system and can't find a controller coz there's no driver for H730 mini. Please advice how to add the drivers on this Live image.