Nagios

Nagios is a very flexible, open-source, network/host monitoring application. Not only does it do reporting on host uptime and services, it can be configured to send emails and text alerts when a system or service goes down or otherwise changes. I've used this within the corporate realm and it fits well - especially among a heterogeneous network like ours.

Nagios' Website

Installation

• NOTE: These installation notes were made during the install to Babbage on August 26th, 2009 by Chris Moore.

mkdir /usr/local/nagios
mkdir /usr/local/nagios-src
wget http://prdownloads.sourceforge.net/sourceforge/nagios/nagios-3.2.0.tar.gz
tar -xvzf nagios-3.2.0.tar.gz

cd nagios-3.2.0

yum install gd mailx 

groupadd nagios -g 812
useradd nagios -u 812 -g 812 -d /usr/local/nagios -s /sbin/nologin

./configure --prefix=/usr/local/nagios --with-nagios-user=nagios --with-nagios-group=nagios --with-command-user=root \
            --with-command-group=root --with-mail=/bin/mailx --with-httpd-conf=/etc/httpd/conf.d --with-init-dir=/etc/init.d \
            --with-gd-lib=/usr/lib --with-gd-inc=/usr/include --enable-statusmap

make all -j 3

make install 
make install-init 
make install-commandmode 
make install-webconf
make install-config #For sample config files