Check client/server connectivity

gistfile1.txt

Stop the service listening on the specific port. Make a server listen on the specified port number by running

```bash
netcat -luv port
```

From a remote host run
```bash
echo "test" | netcat -vu ip port
```

If you the text 'test' gets displayed on the server, then all is good. Otherwise check your security group and local host firewall rules. You can also use tcpdump for troubleshooting

From: http://serverfault.com/questions/678607/udp-tcp-ports-on-aws-ec2-public-ip-blocked