Setting up the cluster
Since the case is pretty much complete now, it is time to take a look at the software. I finally decided to run Raspian on the PIs and Lubuntu on the Banana Pi. While there may be other (maybe even more suitable) OSes available I think is the best starting point for my project. The Banana Pi is equipped with Lubuntu.
After booting the Banana Pi I switched to the German keyboard layout (unfortunately the corresponding GUI is horrible). Afterwards the usual apt-get update
and apt-get upgrade
took care of software updates.
The next steps are the configuration of a static IP as well as the installation of the SSH demon and samba.
EDIT
I just learnt about Bananian which is based on Debian 7. It does not provide a desktop environment, so a 2 GB SD card is said to be sufficient. Since I just want the Bananapi to act as samba server all the Lubuntu features are pretty irrelevant for me.
It also has a sshd running