Kaji for LLN Mote Monitoring

Posted 2014-04-27

Kaji is a generic network monitoring tool that I am adapting for use with a 6LoWPAN LLN network. Kaji really is a repackaging of two network monitoring tools: Shinken for the backend and Adagios for the Web UI. Shinken itself is a Python-based reimplementation of Nagios.

I selected a Shinken-based tool for a few reasons. I enjoy working with Python, and I will need to extend the software for mote monitoring. The close relationship to Nagios provides access to its extensive collection of supporting plugins and tools, like Adagios. Shinken looks to be well managed, too.

LLN Mote Monitoring

The IETF is bringing IP-based networking to constrained nodes in low power wireless networks. Use of IP means it should be possible to adapt a generic network monitoring tool like Kaji/Shinken for use in such a network. Indeed, I am particularly interested in this adaptation due to the value such a tool can bring to LLN network development.

Ping Monitoring

A simple first step for monitoring is to use an ICMP ping to test availability. I have adapted the Nagios check_ping plugin for use with an OpenWSN node. Below are graphs of ping time and failure rate for a mote in a local network.


The adaptation was to recompile check_ping to use 48 bytes of data for the ICMP ping rather than the standard size of 56 bytes. The smaller size was required to fit the message in a single 127-byte 802.15.4 frame, given the extra forwarding header required.

As you can see below, Adagios provides a simple, clear interface for configuration. This page configures the basic Nagios host check command. Notice use of check_ping and the IP address for the mote.