pmacct is a small set of passive network monitoring tools to account, filter, classify, aggregate, and export IPv4 and IPv6 traffic. A pluggable and flexible architecture allows storing collected network data in memory tables, RDBMSs (MySQL, SQLite, PostgreSQL, BDB), and flat files, and also export via IPFIX, NetFlow, or sFlow protocols to remote collectors. pmacct features fully customizable historical data breakdown, sampling, BGP correlation, tagging, and triggers. Libpcap, ULOG, sFlow v2/v4/v5, NetFlow v1/v5/v7/v8/v9, and IPFIX are supported data capturing methods.
Performance Co-Pilot (PCP) is a framework and set of services for supporting system-level performance monitoring and performance management. It provides a unifying abstraction for all of the interesting performance data in a system, and allows client applications to easily retrieve and process any subset of that data using a single API. A client-server architecture allows multiple clients to monitor the same host, and a single client to monitor multiple hosts. Archive logging and replay are integrated so that a client application can use the same API to process real-time data from a host or historical data from an archive.
Webalizer Xtended is a fork of Webalizer and contains a great number of feature improvements, such as monthly statistics for all "HTTP 404 Not Found" errors (including the number of these errors and the corresponding URLs) and additional configuration file keywords. Furthermore, all colors of the statistics can be defined by the user. Webalizer Xtended also fixes several (security-related) bugs in the original Webalizer code and contains the "Apache mod_logio" patch to generate more reliable traffic statistics.
The Logfile Navigator, lnav for short, is a curses-based tool for viewing and analyzing log files. The value added by lnav over text viewers or editors is that it takes advantage of any semantic information that can be gleaned from the log file, such as timestamps and log levels. Using this extra semantic information, lnav can do things like interleaving messages from different files, generate histograms of messages over time, and provide hotkeys for navigating through the file. These features are meant to allow the user to quickly and efficiently focus on problems.
Sendmail Analyzer is a tool to monitor sendmail usage and generate HTML and graph reports. It reports all you ever wanted to know about email trafic on your network. You can also use it in an ISP environment with per domain and per mailbox reports. Statistics are generated per hour, day, month, and year.
Advanced Web Statistics (AWStats) is a free powerful Web server logfile analyzer (Perl script) that shows you all your Web statistics including visits, unique visitors, pages, hits, rush hours, search engines, keywords used to find your site, robots, broken links, and more. It works with both IIS 5.0+ and Apache Web server log files as a CGI and/or from the command line. It also supports around 40 languages.