You can load the ISO image on to the ESXi 5.x or an ESXi 6.0 server after creating the PXE boot VNIC in the PXE boot server profile, modifying the ISO image, and when the PXE server’s configuration file points to the correct files to use for PXE booting.
The ESXi 5.x begins loading all pertinent OS files, and then the server boots to the ESXi 5.x native operating system.
Follow the installer until you are prompted to specify a boot device on the Select a Disk dialog box.
The server's hard disk must be dedicated to the modified ISO. If your server’s hard disk already contains data, a dialog box is displayed warning that data will be overwritten.
You can overwrite the existing data or abort the current installation to store the data on a different device, and then resume the installation.
The Installation Complete dialog box is displayed.
When the server reboots, it progresses through the boot devices until it locates the PXE server’s boot device from which it retrieves the boot image.