If I would like to upgrade the nginx in my current ispconfig installation but also would like to handle rtmp streams I will possible need to recompile and my ngnix on my raspberry Stretch but how do keep it compatible with the current normal installation with ispconfig ? I just need the https://github.com/sergey-dryabzhinsky/nginx-rtmp-module/archive/dev.zip rtmp also and the reguler functions ? Best regards
As soon as your manually compiled nginx uses the same paths for configs, same service name, and same users than the nginx that ships with Debian, then replacing nginx should work.
