# Monitoring and instrumentation

* **Monitoring** is the process of checking if a given system works as expected
* **Instrumentation** is the process of collecting data from a device (link utilisation, CPU utilisation, RAM, disk, …)

The two are related to each other.

## Monitoring tools

TODO

 * Nagios
 * Zabbix
 * Icinga
 * [[https://dev.wlan-si.net/wiki/Nodewatcher|nodewatcher]], an open source network planning, deployment, monitoring and maintenance platform with emphasis on community. 

## Instrumentation tools

 * Munin

### SNMP

TODO

Alternative is to use a simpler channel like [[http://nodewatcher.readthedocs.org/en/latest/telemetry.html |HTTP]]. SNMP is sometimes too big/bloated for small routers.

### Rrdtool

[[http://oss.oetiker.ch/rrdtool/|Round-robin database engine]]

Or use some client-side drawing library, like [[https://github.com/wlanslovenija/django-datastream|django-datastream]].

### Collectd

[[https://collectd.org/|Collectd]] is a nice little program that is able to collect various data on a system, and either write them to a rrdtool database, or send them via the network (or both).

It runs on OpenWRT: [[http://wiki.openwrt.org/doc/howto/statistic.collectd|statistic.collectd]]. This is quite nice with the network-based reporting of the collected data (because you probably don't want to store rrdtool database directly on your OpenWRT routers).