NATS Pi Recipe

Possibly the Smallest NMS in the World

My Pi getting unpacked

This is a recipe to make what is, possibly, the smallest network monitor (NMS) in the world: a NATS Pi with Raspberry Sauce.

Raspberry Pi

First obtain a Model B Raspberry Pi. I was lucky enough to have mine delivered today.

It's a pretty cool bit of kit with an ARM processor, 256Mb of RAM, HDMI, Ethernet, 2 x USB and an SD card reader. More than powerful enough to run FreeNATS so I thought I'd give it a go.

The steps involved were to install the Debian Squeeze OS on the card, set it up as a LAMP server and then install FreeNATS.

Pi Model B on my desk

Installing stuff, before I gave up on X

Install OS

It is possible to buy an SD card with the OS pre-installed but these were out of stock when I ordered.

So I followed the instructions pointed to in the documentation at http://elinux.org/RPi_Easy_SD_Card_Setup to install the Debian OS for it.

LAMP Setup

To setup LAMP I needed to put on Apache, PHP and MySQL.

Before any of this however I needed to update the system with the following commands:

     sudo apt-get update
     sudo apt-get upgrade

Note I actually had to run apt-get update twice for some reason. It also took quite a while.

Apache

The following two commands installed apache2:

     sudo groupadd -f -g33 www-data
     sudo apt-get install apache2

Originally these failed but then I went back and did the update/upgrade step and all was well.

PHP5

To install PHP5 as a CLI and Apache module took the following apt-get with the next commands to ensure www-data could read the web directory:

     sudo apt-get install php5 libapache2-mod-php5
     sudo chown root:www-data /var/www
     sudo chmod 775 /var/www

MySQL

MySQL was the easiest of them all. One command and the setup even prompted to set a root password:

     sudo apt-get install mysql-server

Next Steps

Now I rebooted just to make sure everything was nice and shipshape. I probably didn't need to but the boot time is very quick thanks to small OS and SD install. I also at this point dropped out of X as I was using it to just run a single terminal so a command line would do the job just as well.

Update PHP

To ensure PHP has all the necessary modules for FreeNATS:

     sudo apt-get install php5-mysql
     sudo apt-get install php5-imap
     sudo apt-get install php5-gd
     sudo service apache2 restart

MySQL Setup

Next to setup a MySQL database for FreeNATS and a user with the following commands, XXXX being the MySQL root password set during install:

     mysql -u root -pXXXX
     create database freenats;
     grant all privileges on freenats.* to 'freenats'@'localhost' identified by 'freenats';

FreeNATS Install

For simplicity I decided just to install FreeNATS directly to the web directory so I would access with the URI freenats/server/web/

I switched to root user (sudo su) to avoid sudo'ing all the time which is bad practice but I was feeling reckless. Again XXXX is the MySQL root password.

     cd /var/www
     sudo su
     wget http://www.purplepixie.org/freenats/downloads/freenats-1.14.0a.tar.gz
     tar -xvzf freenats-1.14.0a.tar.gz
     mv freenats-1.14.0a freenats
     cd freenats/server/base/sql
     mysql -u root -pXXXX freenats < schema.sql
     mysql -u root -pXXXX freenats < default.sql
     cd ..

Now to edit the config.inc.php file to update the database connection for the correct credentials (server localhost, user freenats, password freenats, database freenats):

     pico config.inc.php

Finally setup the CRON job:

     cd /etc
     mkdir cron.minute
     cd cron.minute
     pico freenats-tester

Put the following into the freenats-tester script:

     #!/bin/sh
     cd /var/www/freenats/server/bin
     ./test-threaded.sh 2>&1 > /dev/null

Make it executable:

     chmod 755 freenats-tester

Edit the crontab:

     pico /etc/crontab

And add the following line:

     * * * * * root run-parts /etc/cron.minute

Then restart cron to ensure changes have taken effect:

     service cron restart

Voila

One installed NMS on a system no bigger than the credit card with which I purchased it.

Thanks

Most of the LAMP setup stuff was sourced from http://chris-potter.co.uk/2012/05/raspberry-web-server-lamp-stack/ and http://www.raspberrypi.org/phpBB3/viewtopic.php?f=31&t=6294

So thanks.