grub-mknetdir

grub-mknetdir [OPTION...] --net-directory=DIR

--net-directory=DIR
    target directory to create netboot files (required)

--directory=DIR
    source GRUB directory (default: /boot/grub)

--subdir=SUBDIR
    subdir within source directory (default: .)

-?, --help
    display help and exit

--version
    print version information

grub-mknetdir is a GRUB2 utility that generates a complete directory structure for network booting GRUB. It populates the specified output directory with essential files like core images (core.img), modules, fonts, themes, and configuration files needed for PXE, TFTP, HTTP, or iPXE booting.

This tool simplifies deploying GRUB in network environments, such as servers, clusters, or thin clients. It copies assets from the local GRUB installation (typically /boot/grub), resolves dependencies, and organizes them hierarchically (e.g., 1.5/x86_64-efi/ for EFI platforms). The result is a self-contained netboot root that can be served directly by a TFTP server.

Key use cases include automating diskless boot setups or centralizing bootloader distribution. It supports multiple architectures and ensures platform-specific modules (e.g., efi_gop.mod) are correctly placed. Run as root for proper access to source directories.

Requires root privileges for source dirs; ensure TFTP/HTTP server exports the full directory tree. Not all modules included by default—add via grub-mkimage. Fails if source GRUB lacks netboot modules.

grub-mknetdir --net-directory=/var/lib/tftpboot
Generates netboot tree in TFTP root.

Typical layout: DIR/boot/grub/{core.img, fonts/, grub.cfg, i386-pc/, x86_64-efi/, ...}

Introduced in GRUB2 (circa 2009, v1.98+), enhanced in GRUB 2.02+ for better EFI/PXE support. Developed for scalable netboot deployments in Linux distributions like Ubuntu/Debian.

grub-mkimage(1), grub-mkconfig(8), grub-install(8), update-grub(8)