preparing netbsd boot straps from gnu/linux

[pierre-philipp braun <pbraun%nethence.com@localhost>]

Yolo there!

I am trying to prepare a netbsd kernel boot strap at some VPS/IaaS/root-server provider, from the few rescue systems they offer, namely Ubuntu Bionic and FreeBSD 11.1.  I will talk about MULTIBOOT in another message.  This message tackles only native boot strapping.

## Where to get x86 boot loader?

First, I am able to chain `pxeboot_ia32.bin` from SYSLINUX just fine, but it does not seem to be able to load from local disk.  It is only NFS and TFTP aware.  Where to find the standard netbsd boot loader?  I tried to chain `boot` but I get this error

	Booting kernel failed: Invalid argument

What am I missing?  This is the SYS/EXTLINUX config

	label netbsd/boot
	        kernel boot

I could add `append` to append some arguments, but this is probably not how the native bootstrapping works.

The file types of `/usr/mdec/`

	# file -s *
	boot:             DOS executable (COM)
	bootia32.efi:     PE32 executable (EFI application) Intel 80386 (stripped to external PDB), for MS Windows
	bootx64.efi:      PE32+ executable (EFI application) x86-64 (stripped to external PDB), for MS Windows
	bootxx_cd9660:    DOS/MBR boot sector
	bootxx_ext2fs:    DOS/MBR boot sector
	bootxx_fat12:     DOS/MBR boot sector
	bootxx_fat16:     DOS/MBR boot sector
	bootxx_ffsv1:     DOS/MBR boot sector
	bootxx_ffsv2:     DOS/MBR boot sector
	bootxx_lfsv1:     DOS/MBR boot sector
	bootxx_lfsv2:     DOS/MBR boot sector
	bootxx_msdos:     DOS/MBR boot sector
	bootxx_ustarfs:   DOS/MBR boot sector
	dosboot.com:      data
	gptmbr.bin:       SYSLINUX GPT-MBR (version 4.00 or newer)
	mbr:              DOS/MBR boot sector
	mbr_bootsel:      DOS/MBR boot sector
	mbr_com0:         DOS/MBR boot sector
	mbr_com0_9600:    DOS/MBR boot sector
	mbr_ext:          DOS/MBR boot sector
	pxeboot_ia32.bin: DOS executable (COM)

Assuming I get it loaded-up, would this secondary bootstrap be able to access an ext2 file-system?

I just created an a9/netbsd DOS partition and formatted it as ext2.  As for the The NetBSD disklabel, it is not altered as there is no such tool on gnu/linux.  However we get a `e` partition by default, that equals the length of  `c` but has the advantage of being fstype `4.2BSD`.  So I think the following SHOULD work (unless the fstype has to correspond to reality).

	boot hd0:wd0e

-- 
Pierre-Philipp Braun
SNE Russia https://os3.su/