how to install OpenBSD in a computer with Linux and Grub2

[Salvador Fandino]

AFAIK, this procedure is not documented in any place and it is quite
handy in order to install OpenBSD on boxes that already have a recent
Linux inside and use grub2 as the boot manager:

0) do any preparatory work needed: backup your data, resize your
partitions, create a new one for OpenBSD, etc.

1) download bsd.rd and move it to the Linux root partition:

# wget ftp://ftp.openbsd.org/pub/OpenBSD/4.6/i386/bsd.rd
# mv bsd.rd /openbsd.rd

2) add the following entry to /etc/grub.d/40_custom

menuentry "Install OpenBSD from RAM disk" {
set root=(hd0,1)
kopenbsd /openbsd.rd
}

replacing (hd0,1) by the partition id corresponding to the Linux root
file system.

(you may need to modify also /etc/default/grub in order to make grub2
menu visible)

3) regenerate grub configuration:

# update-grub

4) reboot:

# reboot

5) When the grub menu pops up select "Install OpenBSD from RAM disk"


... and install OpenBSD


Cheers,

- Salva

[Vivien MOREAU]

AFAIK, this procedure is not documented in any place [...]

<http://www.openbsd.org/cgi-bin/cvsweb/src/etc/etc.i386/INSTALL.linux?rev=1.15>

:-)

[Aaron Lewis]

Post by Salvador Fandino
AFAIK, this procedure is not documented in any place and it is quite
handy in order to install OpenBSD on boxes that already have a recent
0) do any preparatory work needed: backup your data, resize your
partitions, create a new one for OpenBSD, etc.
# wget ftp://ftp.openbsd.org/pub/OpenBSD/4.6/i386/bsd.rd
# mv bsd.rd /openbsd.rd
2) add the following entry to /etc/grub.d/40_custom
menuentry "Install OpenBSD from RAM disk" {
set root=(hd0,1)
kopenbsd /openbsd.rd
}
replacing (hd0,1) by the partition id corresponding to the Linux root
file system.
(you may need to modify also /etc/default/grub in order to make grub2
menu visible)
# update-grub

I'm on Gentoo Linux , so i think normally you should try with
`grub-mkconfig'
e.g grub-mkconfig > /tmp/grub.cfg && cp /tmp/grub.cfg /boot/grub/grub.cfg

Not all system ships with `update-grub' script.

Post by Salvador Fandino
# reboot
5) When the grub menu pops up select "Install OpenBSD from RAM disk"
... and install OpenBSD
Cheers,
- Salva

[Salvador Fandino]

Post by Vivien MOREAU

AFAIK, this procedure is not documented in any place [...]

<http://www.openbsd.org/cgi-bin/cvsweb/src/etc/etc.i386/INSTALL.linux?rev=1.15>

That is a different thing, the procedure there explains how to boot an
OpenBSD system from grub once it has been already installed on the
machine hard disk.

The procedure I have described shows how to *install* OpenBSD booting
from a RAM disk (bsd.rd) placed in a Linux partition. Basically it
removes the need to create a booting floppy or to burn a CD in order to
install OpenBSD.

- Salva

[Lars Nooden]

The procedure I have described shows how to *install* OpenBSD booting from a
RAM disk (bsd.rd) placed in a Linux partition. Basically it removes the need
to create a booting floppy or to burn a CD in order to install OpenBSD.

It documents how to do it using grub2, which is IMHO much
more complex than old grub.

/Lars

[Luiz Gustavo S. Costa]

AFAIK, this procedure is not documented in any place and it is quite handy
in order to install OpenBSD on boxes that already have a recent Linux inside

Hi, your save my life :-)