Creates a more complete iPXE rom than the one bundled with VirtualBox.
Use docker to build:
docker build -t loader:1 .
docker run --rm loader:1 > vmname.pxe
To use copy to ~/.VirtualBox/TFTP/vmname.pxe and enable Network Boot
in VirtualBox vmname machine.
VirtualBox will load its own iPXE rom that will fetch the one in
~/.VirtualBox/TFTP/vmname.pxe and then this one will fetch iPXE configuration
from file ~/.VirtualBox/TFTP/loader.ipxe.
This makes loading HTTPS roms possible (native VirtualBox iPXE rom is too limiting).
For example to load Rancher use this loader.ipxe file:
#!ipxe
set base-url https://releases.rancher.com/os/latest
kernel ${base-url}/vmlinuz
initrd ${base-url}/initrd
boot
For more details on how VirtualBox handles iPXE see: https://www.virtualbox.org/manual/ch06.html#nat-tftp