tldr/pages/common/nc.md

nc

Netcat is a versatile utility for working with TCP or UDP data. More information: https://manned.org/man/nc.1.

• Establish a TCP connection:

nc {{ip_address}} {{port}}

• Set a timeout:

nc -w {{timeout_in_seconds}} {{ipaddress}} {{port}}

• Scan the open TCP ports of a specified host:

nc -v -z {{ip_address}} {{port}}

• Listen on a specified TCP port and print any data received:

nc -l {{port}}

• Keep the server up after the client detaches:

nc -k -l {{port}}

• Listen on a specified UDP port and print connection details and any data received:

nc -u -l {{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}}

• Send a HTTP request:

echo -e "GET / HTTP/1.1\nHost: {{hostname}}\n\n" | nc {{hostname}} 80