Check manual page of check_tcp

Connection to a TCP Port (unencrypted or with SSL)
Distribution	official part of Check_MK
License	GPL
Supported Agents	Active

This is an active check that connects to any given TCP port and checks if the connection could be established. Therefor it can be used to check nearly any TCP based service on the monitored machine. SSL can be activated to connect to any SSL encrypted service.

Thresholds for the response time can be configured for WARN and CRIT. You can give a string to send over the connection and define a string to expect in the response. A given string to send for terminating the connection can be configured too.

If using SSL you can configure to check for expiration of the SSL certificate within the next days.

This check can be configured by Wato.

Item

The TCP port