How to check if a specific port of a remote host is reachable
sometimes one simply wants to find out if a certain port is reachable and by that a service should be available.
You might use the following command to test
nc -v -z <host|ip> <port> # example: root@ucs:~# nc -v -z ucs-master 53 Connection to ucs-master 53 port [tcp/domain] succeeded! # example - closed port: root@ucs:~# nc -v -z ucs-master 21 nc: connect to ucs-master port 21 (tcp) failed: Connection refused