No, I don’t understand a bit about docker. But when I had a discourse at same VPS where I had Nginx and Varnish before Discourse I used sock without issues. But is it different thing?
Nowadays I have Discourse on different VPS than where is Nginx/Varnish so I can’t use socket. That’s why Varnish sends everyone to port 82 and from there to VPS of Discourse. And that’s why I have:
expose:
- "82:80"
But is even that totally different thing than Discourse can use only ports 80/443?