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justjonathan_15's avatar
justjonathan_15
Icon for Nimbostratus rankNimbostratus
May 04, 2016

Monitoring for a Telnet response?

Hi all,   Is there a way to monitor a port for a telnet response, on say port 7171?   If I run a normal telnet I get the usual blank screen, whereas if it fails I need a monitor to mark it as d...
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IanB's avatar
IanB
Icon for Employee rankEmployee
May 05, 2016

You say that the server doesn't normally send anything back to the client - do you mean it connects and then waits for the client to send something, and only then returns data ? If so, then you could use a telnet monitor to send a particular string and look for a particular reply.

 

If you only want to check whether the TCP three-way-handshake was successful, you can use a TCP monitor with no send or receive string specified. This will only test the 3WHS and nothing more.

 

You could also potentially use a TCP half-open monitor, which sends a SYN, and marks up if it gets a SYN+ACK in reply (if the port is closed, it gets a RST).