OpenBSD 5.7 on BeagleBone Black
-------------------------------

Last edited: $Date: 2015/06/28 10:34:59 $


## BeagleBone Black

The BeagleBone Black (http://beagleboard.org/BLACK) is an Arm-7
development board with a AM335x 1GHz ARM Cortex-A8processor, 512 Mb
DDR3 RAM, ethernet, microD slot, 4GB 8-bit eMMC on-board flash
storage and a lof other nice goodies. This board is capable of
running OpenBSD :)

In order to install OpenBSD on this board, you will need to access
the serial console. This is a 3.3 Volt RS232 serial console, and
connecting this with a 12 or even 5 Volt serial port will be fatal
for the board. You need an USB F-cable to connect the BeagleBone
Black serial port to your laptop or computer.

## Connecting the Serial Port

Locate the pins of the serial board on the BeagleBone Black. The
white dot is next to pin 1.

Use the following pins:

 * pin 1: Ground
 * pin 4: Receive
 * pin 5: Transmit

On this photo: http://box.matto.nl/ftx/bbb-serial.jpg you
can see the USB F-cable connected to the serial console.

I connected the other end (with the USB-connector) with my Debian
Linux laptop and started minicom. In minicom, choose for

 * Baud 115,200
 * Bits 8
 * Parity N
 * Stop Bits 1
 * Handshake None

Boot the board and check that you see the startup-messages.

Bring the board down.

## OpenBSD Installation image

For the BeagleBone Black you need the miniroot-am335x-57.fs
installfile from one of the OpenBSD ftp-mirrors.

You can copy this file with dd to a micro SD-card. I did this on a
Debian Linux laptop with:


   dd if=miniroot-am335x-57.fs of=/dev/mmcblk0 bs=16k


Funny thing is that you can use the same micro SD-card to install
OpenBSD on :)

So you dd the install image to a micro SD-card, start the installer
from there and install OpenBSD on the same card...

## Get the sets

This step is optional, just to make things easier.

I downloaded the setfiles from one of the OpenBSD ftp-mirrors:

 * base57.tgz
 * bsd.OMAP
 * bsd.OMAP.umg
 * bsd.rd.IMX
 * bsd.rd.OMAP
 * bsd.rd.OMAP.umg
 * comp57.tgz
 * game57.tgz
 * index.txt
 * man57.tgz
 * SHA256
 * SHA256.sig

I put these files on a local webserver, so during the install the
installation program can fetch these files from the local network.

I didn't bother to download any x-sets, this board will be running
headless.

## Start the installer

Now the hard work is done. Put the micro SD-card in the slot on the
board. Locate the small switch on to top-side of the board, close to
the micro SD-card slot (on the bottom-side). Keep this switch
pressed while putting power on the board. The board will now attempt
to install from the external micro SD-card and not from the internal
eMMC-flash storage.

The OpenBSD installer will start. Just follow the installation
procedure, I choose the defaults for the partitioning of the SD-card
(it is sd-card 0). After the installation is done reboot.

## Reboot into the installed system

After the reboot, login again via the serial cable and have a look
around your fresh OpenBSD system.

## Protect the micro SD card by mounting it readonly

To protect the life of the SD-card, we are going to make it
readonly.

Make sure your network configuration is right, ssh is hardened and
your ~/.ssh/authorized_keys has the right contents.

Make a directory /proto and copy /var and /home to it.


   mkdir /proto
   cp -rp /var /proto
   cp -rp /home /proto


Now, create a template for /dev



   mkdir /proto/dev
   cd /proto/dev
   cp /dev/MAKEDEV .
   ./MAKEDEV all


Now edit /etc/fstab, comment the entries for /dev, /var and /home out
and make the other entries readonly with noatime option:



   4a6b4c0ba6c86953.b none swap sw
   4a6b4c0ba6c86953.a / ffs ro,noatime 1 1
   4a6b4c0ba6c86953.f /usr ffs ro,noatime,nodev 1 2
   4a6b4c0ba6c86953.g /usr/X11R6 ffs ro,noatime,nodev 1 2
   4a6b4c0ba6c86953.h /usr/local ffs ro,noatime,nodev 1 2
   4a6b4c0ba6c86953.k /usr/obj ffs ro,noatime,nodev,nosuid 1 2
   4a6b4c0ba6c86953.j /usr/src ffs ro,noatime,nodev,nosuid 1 2
   # 4a6b4c0ba6c86953.d /tmp ffs rw,noatime,nodev,nosuid 1 2
   # 4a6b4c0ba6c86953.e /var ffs rw,noatime,nodev,nosuid 1 2
   # 4a6b4c0ba6c86953.l /home ffs rw,noatime,nodev,nosuid 1 2
   swap /dev mfs rw,nosuid,noexec,-P=/proto/dev,-i=128,-s=4096 0 0
   swap /var mfs rw,nosuid,noexec,-P=/proto/var,-s=8192 0 0
   swap /home mfs rw,nosuid,noexec,-P=/proto/home,-s=8192 0 0


Above, 4a6b4c0ba6c86953 is the uuid of the micro SD-card.

Each of the last three lines will make a memory file system (MFS) and
populate that with the corresponding subdirectory from the /proto
diretory.

Reboot and check everything works fine.

## Remounting read/write

In case you want to make some changes. install additional stuff, etc.
you can remount a partition by:



   mount -uw /


In this case / gets remounted read-write.

## Resources

The following pages where helpfull during the installation of OpenBSD
5.7 on the BeagleBone Black:

 * OpenBSD on BeagleBone Black Everything I wish I knew before
   installing the newly renamed armv7 port on a BeagleBone Black by
   Ted Unangst: http://www.tedunangst.com/flak/post/OpenBSD-on-BeagleBone-Black
 * Running OpenBSD off a USB Stick by Volker Roth:
   http://www.volkerroth.com/tecn-obsd-diskless.html
 * OpenBSD on Soekris by John Hart:
   http://blog.spoofed.org/2007/12/openbsd-on-soekris-cheaters-guide.html


$Id: openbsdbeagleblack.txt,v 1.2 2015/06/28 10:34:59 matto Exp $

You are viewing proxied material from box.matto.nl. The copyright of proxied material belongs to its original authors. Any comments or complaints in relation to proxied material should be directed to the original authors of the content concerned. Please see the disclaimer for more details.