Telnet test port is open

[email protected] ~]# Yum list |grep telnettelnet.x86_64                               1:0.17-48.el6               @base   telnet-server.x86_64                        1:0.17-48.el6               base    [[email protected] ~]# which telnet/usr/bin/telnet

[[Email protected] ~]# telnet 123.56.78.103 3306Trying 123.56.78.103...Connected to 123.56.78.103.Escape character is ' ^] ‘. N5.5.40-logxxxxxpassword# proves that port 3306 is open.

[[Email protected] ~]# telnet 123.56.78.103 22Trying 123.56.78.103...Connected to 123.56.78.103.Escape character is ' ^] '. SSH-2.0-OPENSSH_6.6.1P1 ubuntu-2ubuntu2# Proof 22 port development

[[Email protected] ~]# telnet 123.56.78.103 23Trying 123.56.78.103...telnet:connect to address 123.56.78.103:connection Refused# proves that port 23 is not open.

Telnet test port is open