user     :password

devuan:devuan
root      :toor

You just need to add a udev rule, so that the ethernet interface don't get named to a strange name..

cat - <<EOF >> /etc/udev/rules.d/70-persistent-net.rules 
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="yours_maccaddress", ATTR{dev_id}=="0x0", ATTR{type}=="1", KERNEL=="eth*", NAME="eth0"
EOF

Substitute 'yours_maccaddress' with your macaddress..
You cave 3 forms to get it..
boot with that image, attache a display, and a keyboard, and do a ifconfig
or
boot with another image and do a 'ifconfig', and its there,
Or
Use a usb-serial cable attached to the ttyAMA0 uart, and power up the pi and see what comes in the uart

Ground - GPIO 6
Tx         - GPIO 8
RX        - GPTI 10

then use for example picocom to connect to the uart:
apt-get install picocom

#picocom /dev/your_tty_device -b 115200

And only then apply power to the board.. and see wat is comming in the uart, its the best tool for debug

remember:
Tx means board TX( which means it needs to be conected to usb-serial RX )
Rx means board RX( which means it needs to be conected to usb-serial TX )

in the meantime you can try the image I proposed
and say something about it

Best Regards,
tux

Does you have a usb-serial cable to do some debug on that Image?
Does you experimented the image here: http://arm-files.devuan.org/

I probably have a usb-serial cable somewhere, but I do not know how to debug. Is there any guide somewhere?
I checked these new beowulf images, but there is none for RPi 2 yet. Nevertheless, I expected an older/tested image on an older RPi version to work smoothly.

Does you experimented the image here: http://arm-files.devuan.org/

It shows the initial color screen and then goes blank and stops.
There is no green led activity after this.

Can anyone point me to the right direction?