[ Thanks to Lee
Schlesinger for this link. ]
“Every organization must monitor its infrastructure?s uptime and
performance. While the popular Nagios application is a good
general-purpose monitoring program that you can extend with plugins
to handle just about any task, you may do even better by employing
Cacti as a graphical front end to RRDTool?s data logging and
graphing functionality. Cacti was developed specifically to monitor
and collect performance information, while Nagios is more oriented
toward state changes, such as noting whether a daemon is up or
down.“RRDTool stores all of the necessary information to create
graphs and populate them with data in a MySQL database. Cacti
provides templates to gather and show information such as system
load (CPU, RAM, disks), users connected, MySQL load, and Apache
load, all of which can affect the performance of your site.”