View source for System Monitoring and Server Statistic Software

This article started off as a brain-dump by Wen Hao Chuang. Hopefully more people will contribute to this article in the near future.

The [http://www.mrunix.net/webalizer/ Webalizer]
The Webalizer is a fast, free web server log file analysis program. It produces highly detailed, easily configurable usage reports in HTML format, for viewing with a standard web browser.

[http://www.nagios.org/ Nagios]
Nagios is a host and service monitor designed to inform you of network problems before your clients, end-users or managers do. It has been designed to run under the Linux operating system, but works fine under most *NIX variants as well. The monitoring daemon runs intermittent checks on hosts and services you specify using external "plugins" which return status information to Nagios. When problems are encountered, the daemon can send notifications out to administrative contacts in a variety of different ways (email, instant message, SMS, etc.). Current status information, historical logs, and reports can all be accessed via a web browser.

[http://munin-monitoring.org/]
Munin is a networked resource monitoring tool that can help analyze resource trends and "what just happened to kill our performance?" problems. It is designed to be very plug and play. A default installation provides a lot of graphs with almost no work.

[http://www.ibm.com/developerworks/aix/library/au-analyze_aix/]
The nmon tool is designed for AIX and Linux performance specialists to use for monitoring and analyzing performance data.