netcat

• nc [options] host port

• udp: nc -u host port

• Port Scanning: nc -z -v 10.10.8.8 20-80. The -z option will tell nc to only scan for open ports, without sending any data to them and the -v option to provide more verbose information.

• nc -z -v 10.211.55.2 8070-8080 2>&1 |grep succeeded

• UDP Port Scanning: nc -z -v -u 10.10.8.8 20-80