NGINX behind NGINX-Proxy: Getting connection refused - docker

Question

I want to use nginx-proxy in front of another nginx (my-nginx) instance and this is the most minimal problem setup I can come up with. I am on the same machine and have the following:
Setup
NGINX-Proxy docker-compose.yml
version: '3.8'
services:
nginx-proxy:
image: jwilder/nginx-proxy
ports:
- "80:80"
volumes:
- /var/run/docker.sock:/tmp/docker.sock:ro
networks:
- nginx-proxy
networks:
nginx-proxy:
external: true
Network
docker network create nginx-proxy
Commands
These are the commands that I run to start the nginx-proxy and my-nginx
docker compose up -d
and (I made this as minimal as possible, actually this NGINX is part of a larger docker compose project, but the error connection refused remains)
docker run -p 888:80 --network nginx-proxy -e VIRTUAL_HOST=my.sub.domain.tld -e VIRTUAL_PORT=888 --name my-nginx nginx
Logs
docker ps shows me that both containers are working
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
744f4df7059d nginx "/docker-entrypoint.…" 4 minutes ago Up 4 minutes 0.0.0.0:888->80/tcp, :::888->80/tcp my-nginx
e3c57213f2bc jwilder/nginx-proxy "/app/docker-entrypo…" 5 minutes ago Up 5 minutes 0.0.0.0:80->80/tcp, :::80->80/tcp jwilder-nginx-proxy-1
And this docker network inspect nginx-proxy tells me that they are infact connected to the same network.
[
{
"Name": "nginx-proxy",
"Id": "f71dcf5c1125005f1527eaa6c47d77c4aeeafb763faefc17c42e10b73c23d52b",
"Created": "2022-11-08T18:36:31.022872372Z",
"Scope": "local",
"Driver": "bridge",
"EnableIPv6": false,
"IPAM": {
"Driver": "default",
"Options": {},
"Config": [
{
"Subnet": "192.168.208.0/20",
"Gateway": "192.168.208.1"
}
]
},
"Internal": false,
"Attachable": false,
"Ingress": false,
"ConfigFrom": {
"Network": ""
},
"ConfigOnly": false,
"Containers": {
"744f4df7059d02aa0b805a769fbc8b6428c0f3ace165b89d4b3c93395d517e72": {
"Name": "my-nginx",
"EndpointID": "7252798a05774d3d07ce04524859820026f9bad93b0b72d0350033fad821d285",
"MacAddress": "02:42:c0:a8:d0:03",
"IPv4Address": "192.168.208.3/20",
"IPv6Address": ""
},
"e3c57213f2bcbe70e91c961492c4157d6fc1f4f1a5c6456969201b102d689442": {
"Name": "jwilder-nginx-proxy-1",
"EndpointID": "5e41bc5c60c6b3d697e70f32b443e9c5b2852ae6c6099ad21a5ef978981cf9be",
"MacAddress": "02:42:c0:a8:d0:02",
"IPv4Address": "192.168.208.2/20",
"IPv6Address": ""
}
},
"Options": {},
"Labels": {}
}
]
Problem
When I exec into the nginx-proxy with
docker compose exec nginx-proxy bash
and I try to curl my-nginx with
curl my-nginx:888
I get:
curl: (7) Failed to connect to my-nginx port 888: Connection refused
What I tried:
use the default network instead of nginx-network
curl from host (does not work)
access via internet gives this error (the same issue as the above curl)
jwilder-nginx-proxy-1 | nginx.1 | 2022/11/09 10:02:39 [error] 38#38: *7 connect() failed (111: Connection refused) while connecting to upstream, client: 84.56.95.53, server: my.sub.domain.tld, request: "GET / HTTP/1.1", upstream: "http://192.168.208.3:888/", host: "my.sub.domain.tld"
jwilder-nginx-proxy-1 | nginx.1 | my.sub.domain.tld 84.56.95.53 - - [09/Nov/2022:10:02:39 +0000] "GET / HTTP/1.1" 502 157 "-" "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:106.0) Gecko/20100101 Firefox/106.0" "192.168.208.3:888"
Any help is much appreciated!