Whatever your reason for placing an NGINX proxy in front of your Gitlab installation, you need to ensure you’re using the right configuration to support all of Gitlab’s features. I recently discovered that although my installation was mostly working I couldn’t get pipeline/build logs properly. I discovered that my proxy configuration was to blame. After some searching around I finally found that my config wasn’t quite right. To get the most out of Gitlab and ensure a smooth experience use configuration shown below as a template for your own. In my setup I use LetsEncrypt for SSL so if you’re not you can remove any of the SSL specific parts. The important configuration information is contained the the location block.

upstream gitlab {
  server <ip of your gitlab server>:<port>;
}

server {
    listen          443;
    server_name     <your gitlab server hostname;

    ssl on;
    ssl_certificate <path to cert>;
    ssl_certificate_key <path to key>;
    ssl_protocols TLSv1 TLSv1.1 TLSv1.2;
    ssl_prefer_server_ciphers on;
    server_tokens off;


    gzip on;
    gzip_vary on;
    gzip_disable "msie6";
    gzip_types application/json;
    gzip_proxied any;
    gzip_comp_level 6;
    gzip_buffers 16 8k;
    gzip_http_version 1.1;

    location / {
       client_max_body_size   0;
       proxy_set_header    Host                $http_host;
       proxy_set_header    X-Real-IP           $remote_addr;
       proxy_set_header    X-Forwarded-Ssl     on;
       proxy_set_header    X-Forwarded-For     $proxy_add_x_forwarded_for;
       proxy_set_header    X-Forwarded-Proto   $scheme;

      proxy_pass https://gitlab;
    }
}

This configuration will properly pass all requests through to your Gitlab server as well as allow CI/CD pipeline logs to pass through properly.