Netboot

From ArchWiki

Netboot images are small (< 1 MiB) images that can be used to download the latest Arch Linux release on the fly upon system boot. It is unnecessary to update the netboot image, the newest release will be available automatically. Netboot images can be downloaded from the Arch Linux Netboot page.

Note: You need sufficient memory (probably 1.5GiB or even more) to store and run the live system, otherwise you may get a kernel panic on boot.

BIOS

To use netboot on a BIOS-based computer, you need either the ipxe.lkrn or ipxe.pxe image.

Using ipxe.lkrn

The ipxe.lkrn image can be booted like a Linux kernel. Any Linux boot loader (like GRUB or Syslinux) can be used to load it from your hard drive, a CD or a USB drive. For example, the Syslinux wiki gives instructions to install[1] and configure[2] Syslinux on a bootable medium.

You can make flash drive that boots ipxe.lkrn with the following steps:

  • Find out your device path using lsblk. Let us assume it is /dev/sdc.
  • Create MBR partition table on the device.
  • Create a primary partition with FAT32 file system and flag it as active.
  • Mount partition, create boot/syslinux directory there and copy ipxe.lkrn to the boot directory.
# mount /dev/sdc /mnt
# mkdir -p /mnt/boot/syslinux
# cp ipxe.lkrn /mnt/boot
  • Create syslinux configuration
/mnt/boot/syslinux/syslinux.cfg
DEFAULT arch_netboot
   SAY Booting Arch over the network.
LABEL arch_netboot
   KERNEL /boot/ipxe.lkrn
  • Unmount partition
# umount /mnt
  • Install Syslinux MBR and Syslinux itself
# dd bs=440 count=1 conv=notrunc if=/usr/lib/syslinux/bios/mbr.bin of=/dev/sdc
# syslinux --directory /boot/syslinux/ --install /dev/sdc1
  • Now you should be able to boot your usb stick with ipxe.lkrn.

Alternatively, you can also try the image with QEMU by running the following command: 

$ qemu-system-x86_64 -enable-kvm -m 2G -kernel ipxe.lkrn

Using ipxe.pxe

The ipxe.pxe image is a PXE image. It can be chainloaded from an existing PXE environment. This allows configuring a DHCP server such that booting from the network will always boot into Arch Linux netboot.

Alternatively, you can also chainload it from existing pxe loader such as pxelinux. This is a menu entry example: 

LABEL arch_netboot_chain
  COM32 pxechn.c32
  APPEND ipxe.a56af4e6a9a9.pxe

For this example to work you must have pxechn.c32 copied to the directory where your pxelinux.0 resides.

UEFI

The ipxe.efi image can be used to launch Arch Linux netboot in UEFI mode. Only 64-bit UEFI is supported. The ipxe.efi image can be added as a boot option via efibootmgr, launched from a boot manager, like systemd-boot or rEFInd, or directly from the UEFI shell.

Installation with efibootmgr

First install the efibootmgr package, then download the UEFI netboot image.

Assuming your EFI system partition (ESP) is /dev/sdd1 and mounted under esp, you should move it as follows—let us also give it a more friendly name: 

# mkdir esp/EFI/arch_netboot
# mv ipxe.*.efi esp/EFI/arch_netboot/arch_netboot.efi

Then you can create a boot entry as follows: 

# efibootmgr --create --disk /dev/sdd1 --part 1 --loader /EFI/arch_netboot/arch_netboot.efi --label "Arch Linux Netboot" --verbose