I have testet the installation with actually 19.1.29190917 (standard: apache as reverse-proxy, MariaDB) on CentOS 7.1810 minimal. Works perfect.
But it is absolutely necessary to follow the (installation) instructions:
CentOS is a bit more complicated than for example Debian (my favorite).
I have simplified this in the graphics a bit, so that it is generally better to understand:
EGroupware runs in the Docker-install on an Nginx-server (as described in the text). That’s why the Nginx container. Your Apache is configured as reverse-proxy.
I understand that. I also have to learn something new in Docker. It’s also not my world yet (My cup of coffee )
The installation should now also work on CentOS. Unfortunately nobody agreed to test the installation under CentOS after our call for the beta test. And we don’t manage to test everything in detail. CentOS/RHEL are only used by a few and that is a bit special. But you don’t have to fight with EPEL/PHP anymore for that with Docker
But that’s the way to distibute applications today. You will hardly be able to avoid it in the long run.
But you need very little Docker know-how for the EGw-Docker installation. We will (have to) document even more.