Creating A USB Bootable Modified Netinstall ISO Image

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3 thoughts on - Creating A USB Bootable Modified Netinstall ISO Image

  • I think you’d need to use the “isohybrid” command that’s included in the syslinux package. From /usr/share/doc/syslinux-4.04/isolinux.txt:

    ++++ HYBRID CD-ROM/HARD DISK MODE ++++

    Starting in version 3.72, ISOLINUX supports a “hybrid mode” which can be booted from either CD-ROM or from a device which BIOS considers a hard disk or ZIP disk, e.g. a USB key or similar.

    To enable this mode, the .iso image should be postprocessed with the
    “isohybrid” script from the utils directory:

    isohybrid filename.iso

    This script creates the necessary additional information to be able to boot in hybrid mode. It also pads out the image to an even multiple of 1 MB.

    This image can then be copied using any raw disk writing tool (on Unix systems, typically “dd” or “cat”) to a USB disk, or written to a CD-ROM using standard CD burning tools.

    The ISO 9660 filesystem is encapsulated in a partition (which starts at offset zero, which may confuse some systems.) This makes it possible for the operating system, once booted, to use the remainder of the device for persistent storage by creating a second partition.

    -Greg

  • BING! BING! BING! We have a winner! Thanks for that info, it makes the USB stick bootable. This will make kickstart installations so much easier, especially for systems that don

  • Alfred von Campe writes:

    It would be interesting to see a comparison of fdisk -l for USB treated without and with isohybrid. I previously found that USB drives would not boot if the boot partition doesn’t start on block 1; most tools, including fdisk and gparted, seem to put the start of the partition on much higher blocks when used on USB drives.