upstream exampleorg {
            server 127.0.0.1:8087;
    }
    server {
        listen 80;
        server_name www.example.org;

        # content
        # - static
        root /var/web/example.org/www/res;

        # - main webserver
        error_page 403 404 @exampleorg;
        error_page 502 /../502.html;
        location @exampleorg {
            proxy_pass http://exampleorg;
            proxy_redirect off;

            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
            proxy_set_header X-Forwarded-Proto $scheme;
        }
    }

error_page 502 /502.html;
        location /502.html {
            root /var/web/example.org/www;
            internal;
        }