EEM or TCL script to test for open port

[Nathan Mellendorf]

Hello all,

Has anyone had success with developing a script to test for an open port? For example, I'd like to use my router to ocasionally check if port 3389 is open on 192.168.1.1. I've scripted a few tests already, but this is the one thing that I haven't been very successful in completing. 

Any and all suggestions / support are welcome. Thanks in advance to anyone who's able to assist.

[Joe Clarke · Accepted solution]

Here's some simple EEM Tcl code that should work:

::cisco::eem::event_register_timer watchdog time 3600

namespace import ::cisco::eem::*

namespace import ::cisco::lib::*

if { [catch {socket 192.168.1.1 3389} result] } {

    action_syslog msg "tcp/3389 on 192.168.1.1 is no longer open"

}

set fd $result

close $fd

action_syslog msg "tcp/3389 on 192.168.1.1 is open"

[Nathan Mellendorf]

Joseph,

As always, thank you very much for your effort and assistance on this.

I ran the following in tclsh and it worked great.

catch {socket 74.125.225.83 443} result

I had omitted another peice of the puzzle, but I was able to find the solution. I needed to source the socket request from a certain interface. Here is what I found:

catch {socket -myaddr 192.168.1.1 74.125.225.83 443} result

Thanks again!