NGINX UDP Proxy listening same port and decides on origin ip-CodePudding

I am currently trying to make a nginx proxy work where it pass to different ips depending on the origin.

stream {
    server {
        listen 1000 udp;
        proxy_pass 10.0.0.2;
        allow 10.0.0.3;
    }
    server {
        listen 1000 udp;
        proxy_pass 10.0.0.3;
        allow 10.0.0.2;
    }
}

obviously this does not work as I can not listen on the same port twice. I tried something with "if" but it is not allowed there. Any ideas? I just want to proxy the traffic between the two ips.

CodePudding user response：

You need transparent proxy or some kind of packet filter or firewall, not nginx, since it is reverse proxy and not suitable for your task.

CodePudding user response：

While I'm not sure you choose the right way to solve your task (unless you need some kind of load-balancing), however this this should be possible using several upstream blocks and the geo block:

stream {
    upstream first_upstream {
        server 10.0.0.2:1000;
    }
    upstream second_upstream {
        server 10.0.0.3:1000;
    }
    upstream third_upstream {
        server 10.0.0.4:1000;
    }
    geo $upstream_name {
        10.0.0.0/24  first_upstream;
        10.0.1.0/24  second_upstream;
        default      third_upstream;
    }
    server {
        listen 1000 udp;
        proxy_pass $upstream_name;
    }
}

If you need a load-balancing, see the TCP and UDP Load Balancing article.