How to close port 22 ?

[Olivier Nicole]

Khun Jarungwit,

The file /etc/services tells you what is the port number for some
known services. The file /etc/services is not the file that start the
services.

In the file /etc/rc.conf you must put a line:

sshd_enable="NO"

to remove SSH.

But I strongly suggest that you use SSH instead of telnet to allow
remote connection to your machine.

Best regards,

Olivier