nc

Netcat is a versatile utility for working with TCP or UDP data. More information: https://nmap.org/ncat.

Listen on a specified port and print any data received:

nc -l {{port}}
Connect to a certain port:

nc {{ip_address}} {{port}}
Set a timeout:

nc -w {{timeout_in_seconds}} {{ipaddress}} {{port}}
Keep the server up after the client detaches:

nc -k -l {{port}}
Keep the client up even after EOF:

nc -q {{timeout}} {{ip_address}}
Scan the open ports of a specified host:

nc -v -z {{ip_address}} {{port}}
Act as proxy and forward data from a local TCP port to the given remote host:

nc -l {{local_port}} | nc {{hostname}} {{remote_port}}