test connection if ICMP is disabled

telnet <ip> <port>
Telnet will make a tcp connection to a remote ip/port to test connectivity. If it times out, it's not reaching the host (maybe the firewall is blocking it). If connection is refused, it's reaching the host, but either the service is not listening on that port, or it's locked.
Sample Output
$ telnet 80
Connected to localhost.
Escape character is '^]'.

2009-02-12 19:11:03

What Others Think

This is useful if you are certain the port is listening (to test connectivity); or to test whether the port is listening (test service). It's also very useful to test connectivity when ICMP is blocked at the firewall.
nicdev · 635 weeks and 3 days ago
i don't understand why the negative votes. this command works well and it is very usefull!
andreisid · 467 weeks ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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