This post discusses the software used in the Hexnut robot.
The primary computation is performed by a Raspberry Pi.
I started with a freshly installed Debian Wheezy release that had been updated and upgraded.
The first thing I wanted was a way to collect (and eventually monitor) statistics about the system. For this I decided to use collectd
$ sudo apt-get install collectd
The syslog starting showing many errors related to rrdtool that looked like this:
rrdtool plugin ... failed ... illegal attempt to update using time ... when last update time is ... (minimum one second step)
So I edited the collectd configuration to disable all plugins. I will enable the plugins as they are needed.
graphite and carbon
I want to use graphite to display the statistics. I installed graphite-carbon using:
$ sudo apt-get install graphite-carbon
I tried installing graphite-web in the same way, but the package wasn’t found:
$ sudo apt-get install graphite-web E: Unable to locate package graphite-web
I looked at the graphite-web documentation and it suggested using virtualenv and pip to install graphite-web.
To do that I first needed to install the python-virtualenv package for python 2.7.3
$ sudo apt-get install python-virtualenv
I then created a virtualenv for graphite and activated it:
$ sudo virtualenv /opt/graphite $ sudo source /opt/graphite/bin/activate
I then was able to install graphite-web using
(graphite)$ sudo pip install https://github.com/graphite-project/ceres/tarball/master (graphite)$ sudo pip install whisper (graphite)$ sudo pip install carbon (graphite)$ sudo pip install graphite-web