...

stream {

server {
        listen 172.16.17.11:1010 udp;
        proxy_pass udpstream1;
        proxy_bind $remote_addr:$remote_port transparent;
        }

server {
        listen 172.16.17.11:1011 udp;
        proxy_pass udpstream2;
        proxy_bind $remote_addr:$remote_port transparent;
		}

upstream udpstream1 {
		server 192.168.17.11:1010;
		server 192.168.17.12:1010;
		server 192.168.17.13:1010;
		}

upstream udpstream2 {
		server 192.168.17.11:1011;
		server 192.168.17.12:1011;
		server 192.168.17.13:1011;
		}
		
		
		
}

...