I’m running the latest version of Nagios and plugins and I’m pretty new at running it.
I would like to use check_tcp to check the availability of a TCP port on a server. But there is a catch. When I get a “connection refused” respose, I would like to signify that it is UP, and when I get a “TCP OK” response, that that it is DOWN. I have it setup monitoring the port, but is there a way to “inverse” or “reverse” the results of check_tcp?