Is it possible to add some 'PXE Network Boot' option to GRUB?

Question

This is an example of my available GRUB menu boot options:

 1     menu label   ^  1) Xubuntu 14.04.02 LTS
 2     menu label   ^  2) Windows 7, x86 & AMD64
 3     menu label   ^  3) Windows 8, AMD64
 4     menu label   ^  4) Hirens Boot CD 8.8, x86
 5     menu label   ^  5) Kali 1.0.7 Live, amd64

In order to repair/reconfigure/rescue servers or machines without keyboard&screen, it would be very useful to be capable of booting remote machines to PXE Network without needing to physically go near the computer to select the PXE option in the BIOS.

Adding a PXE Network Boot option to GRUB would be fantastic. Something like:

 1     menu label   ^  1) Xubuntu 14.04.02 LTS - Sopalajo Mod, amd64
 2     menu label   ^  2) Windows 7, x86 & AMD64
 3     menu label   ^  3) Windows 8, AMD64
 4     menu label   ^  4) Hirens Boot CD 8.8, x86
 5     menu label   ^  5) Kali 1.0.7 Live, amd64
 6     menu label   ^  6) PXE Network server on this LAN

I am patching the problem for now by selecting PXE as the first boot option in the BIOS, but I don't always want PXE as the first boot option.
As long as GRUB includes some really useful programs like grub-reboot or, at least, accepts remote reconfiguration, adding PXE to GRUB could be a perfect solution.

Is it possible to add a PXE option to the GRUB boot menu?

Answer 1

Yes, you can add a (i)PXE Launcher to Grub.

For dpkg-based systems like Debian&derivatives: Only apt-get install ipxe is required

I would expect other distros to have integrated it as well fairly comfortably.

==> A "PXE Boot" menu entry will exist on next reboot.

In case you want to know inner-working-details:

The post-install hook scripts automatically adds an iPXE entry to the grub configuration, using the "template" file /etc/grub.d/20_ipxe.

You end up with an entry like the following in /boot/grub/grub.cfg

menuentry 'Linux NetBoot Environment' {
  set root='(hd0,1)'
  <More, less important options>
  linux16 /boot/ipxe.lkrn
}

This just means, that instead of a (linux-)kernel, grub gives full computer control to another "simple" program, in this case ipxe.lkrn. MemTestx86 is launched in basically the same way.

The PXE Stack is software normally stored somewhere on the main-board. Just in this case we load it from somewhere the drivers from GRUB can access.

Example of a usage scenario:

You will want to install a basic GRUB on the drive, having the PXE entry first, and a fall-back on Position 2 to local chain-boot from (say) Partition 1.

The configuration iPXE would use will then depend on the files residing on your boot-configuration-server. There you will make the default, first menuchoice "Boot from local Partition 1", then more choices (Boot-AV, SuperGrub, Debian NetInst...).

==> Your Users normally don't touch anything until they see the Graphical Login Prompt from the local Installation.

Boot-Sequence: GRUB - iPXE - OS-in-Partition-1 (Fallback to OS-In-Partition-1, if PXE unsuccessful)

==> Physically present at the PC, you could choose other Boot-Options.

==> Not physically present at the PC, you can change the server-side PXE configuration to "one-off" boot another choice than the default.

Answer 2

For recent versiones of iPXE efi chainloading is possible. In the ipxe.iso is an image (esp.imp) which contains the needed efi structure. You can copy the BOOTX64.EFI file to a different place in your EFI partition and chainload it with grub.

Answer 3

Generally, I have found the PXE boot option only exists on a system BIOS boot selection menu. Once you get into grub it is basically too late.

On Dell machines, it looks to be possible to program this action remotely (and programatically) depending on the hardware you have installed. Especially using the Dell iDRAC. This capability might be possible on other vendor hardware as well.