Netcat, is the Swiss army knife of connections between servers.
It can listen, connect and launch shells.
Older versions had the -e or -c option to launch a shell. Recent versions do not have this option anymore for security reasons.
On Kali there is a version 1.10 in :
/usr/bin/nc -h -e shell commands : program to execute -c shell commands : program to execute -l : listen mode -v : verbose -p port : local port number
Connect to port 3000 on 10.0.0.11 server:
/usr/bin/nc 10.0.0.11 3000