# multi-booting with NT

• To: misc@openbsd.org
• Subject: multi-booting with NT
• From: Jim Rees <rees@umich.edu>
• Date: Thu, 07 May 1998 11:48:14 -0400
• Delivery-Date: Thu May 7 08:50:06 1998

```It seems the NT loader can be used to boot OpenBSD.  You just have to make a
copy of the first sector (the PBR) of the OpenBSD part of the disk, put it
in a file in the NT file system, and add a line to boot.ini.  Something like
this (assume the NT partition is mounted at /c):

/usr/mdec/installboot ...
dd if=/dev/rsd0a of=/c/openbsd.pbr count=1
echo 'c:\openbsd.pbr="OpenBSD"' >>/c/boot.ini

Now when you boot, OpenBSD will be one of the choices on the NT loader
screen.  You have to re-do this any time you run installboot, since that's
what makes the pbr.

You do not want to install the OpenBSD mbr (fdisk "update").  Apparently the
NT mbr is special, and although some people report they have been able to
boot NT with the OpenBSD mbr, it doesn't work for me.  I just get the