Check status of one port on remote host [closed]

Answer 1

You seem to be looking for a port scanner such as nmap or netcat, both of which are available for Windows, Linux, and Mac OS X.

For example, check for telnet on a known ip:

nmap -A 192.168.0.5/32 -p 23

For example, look for open ports from 20 to 30 on host.example.com:

nc -z host.example.com 20-30