After I got some experience with hosting OpenStreetMap tiles during the revival of Openptmap, I wanted to dig deeper into the topic in order to firstly migrate Openptmap to the new flex output so that it can receive incremental updates, and secondly to be able to host some additional overlays.
I found that the only widely used way to host tiles is overv/openstreetmap-tile-server. On the first look, it is really easy to use. It takes care of importing and updating the OSM database and of rendering and serving the tiles. On the second look however, there are some major challenges and problems with it: