You can customize the standard ESXi installer ISO image with your own installation or upgrade script. This enables you to perform a scripted, unattended installation or upgrade when you boot the resulting installer ISO image.

Linux machine.

The ESXi ISO image VMware-VMvisor-Installer-5.x.x-XXXXXX.x86_64.iso,where 5.x.x is the version of ESXi you are installing, and XXXXXX is the build number of the installer ISO image.

Your custom installation or upgrade script, the ks_cust.cfg kickstart file.


Download the ESXi ISO image from the VMware Web site.


Mount the ISO image into a folder:

mount -o loop VMware-VMvisor-Installer-5.x.x-XXXXXX.x86_64.iso /esxi_cdrom_mount

XXXXXX is the ESXi build number for the version that you are installing or upgrading to.


Copy the contents of cdrom to another folder:

cp -r /esxi_cdrom_mount /esxi_cdrom


Copy the kickstart file to /esxi_cdrom

cp ks_custom.cfg /esxi_cdrom


(Optional) Modify the boot.cfg file to specify the location of the installation or upgrade script using the kernelopt option.

This step makes the installation or upgrade completely automatic, without the need to specify the kickstart file during the installation or upgrade.


Recreate the ISO image:

mkisofs -relaxed-filenames -J -R -o custom_esxi.iso -b isolinux.bin -c -no-emul-boot -boot-load-size 4 -boot-info-table /esxi_cdrom

The ISO image now includes your custom installation or upgrade script.

Install ESXi from the ISO image.