Ok. Thanks so far. CUPS is listening on port 631 and I can get to it via wget from my max2play device (odroid), so the service seems to be Ok and running – but I cannot reach it from any other device in my network (Notebook, iPad, PC…) . So maybe it is some firewall issue? I only have a FritzBox router, I thought there was no port blocking or additional firewall there in my local network. Does anyone have any more ideas?