Nginx 作为 docker 容器内的反向代理

Question

I'm trying to use nginx as a reverse proxy inside a container points to the different PHP application container. My PHP container gets requests from external port 8080 and forwards it to internal 80. I want my nginx to get listen to port 80 and forward the request to the PHP container on port 8080 but have issues redirecting the request.

My nginx Dockerfile:

FROM nginx:latest
COPY default.conf /etc/nginx/conf.d/default.conf

My nginx default.conf:

server {
  listen 80;
  error_page 497 http://$host:80$request_uri;
  client_max_body_size        32M;
  underscores_in_headers      on;

  location / {
    proxy_set_header    X-Forwarded-Host   $host; 
    proxy_set_header    X-Forwarded-Server $host; 
    proxy_set_header    X-Forwarded-For    $proxy_add_x_forwarded_for; 
    proxy_set_header    X-Forwarded-Proto  $scheme; 
    proxy_set_header    X-Real-IP          $remote_addr; 
    proxy_set_header    Host               $host;

    proxy_pass          http://php-container:8080;
    proxy_read_timeout  90;
    proxy_http_version  1.1;
    }
}

I've tried deploying it via docker-compose with the above yml file, but got the same error when CURL to the nginx.

When CURL to HTTP://localhost:8080 (PHP application) and also to HTTP://localhost:80 (nginx) there's a log output from the docker-compose log.

But when CURL to nginx, I got the above error:

Answer 1

You have a misconfiguration here.

nginx (host:80 -> container:8080)

php-app (host:8080 -> container:80)

Nginx can't reach of "localhost" of another container because it's a different container network.

I suggest you create a docker network --network and place both containers to the network. Then in Nginx config, you can refer php-app container by name.

    proxy_read_timeout      90;
    proxy_redirect          http://localhost:80/ http://php-container:8080/;

Besides you can expose only the Nginx port and your backend will be safe.