Thanks for bringing this up.
We don't directly support monitoring of kannel/smpp. Alternatively, you can write a plugin or download the Nagio's Kannel plugin to monitor the same.
Writing a Plugin:
Using our Custom Plugin, you can write your own plugin and monitor the Kannel/smpp locally or remotely.
Writing a plugin for Linux -
Writing a plugin for Windows -
Download Nagios plugin:
You can also download the Nagios's Kannel Plugin and integrate it with our Linux agent and monitor the same.
Steps for integrating the Nagios plugin with our Linux agent:
Hope this fulfill your requirements. For further queries, comment below.