Anteater is a log analyser for MTA logfiles (such as those produced by sendmail and postfix). The tool is written in 100% C++ and is very easy to customize. Input, output, and the analysis are modular class objects with a clear interface. Currently, there are modules for reading the syslog format of sendmail and postfix that do up to eight useful analyses and write the result in plain ASCII or HTML, to stdout or to files.
Diald manages network links, particularly on-demand links such as dial-up SLIP or PPP. It can also be used to manage and/or monitor any network interface. Diald monitors traffic on the link and makes intelligent (and highly configurable) decisions as to when the link should be brought up or taken down. The included control program, dctrl, runs on any system with Tcl/Tk (yes, even Windows) and allows diald to be controlled and monitored remotely.
LineControl allows you to remotely control the Internet connection of a Linux masquerading server using multiple clients. It takes care with the number of clients using the connection and decides upon this number whether the connection should be up or down. The clients show the time the connection is up and throughput statistics. Different connection types are supported, such as analog modems, ISDN, or even cable modems and ADSL devices.
pflogsumm.pl is designed to provide an over-view of postfix activity, with just enough detail to give the administrator a "heads up" for potential trouble spots. Reports includes: Total number of messages and bytes; Hosts/Domains; senders and Recipients; per-hour traffic reports; summaries of warnings, fatal errors, and panics; and so on ...
popexec is a program for Unix/Linux which checks a POP e-mail account and then runs a program whenever new e-mail arrives. It can also optionally run a program when it sees that you no longer have new e-mail in your POP box. Examples are included which show you how to: Write "You have mail" or "You have X new messages" to a terminal, make a terminal beep, play an audio file, pop an X window onto the screen, make your keyboard LEDs blink, change your desktop background.
Smit is an ARP-level transproxy/sniffer, capable of relaying local traffic even in switched environment. The source is based on the arprelay and arpmitm tools, but offers a nice command line interface and option of saving raw packets into a file. It includes some tricky techniques for ARP-cache consistence. You can also run Smit in transproxy-only mode and use your favourite sniffer to capture 'hijacked' packets, and it includes a ring buffer option for high performance packet capture.
scponly is an alternative "shell" of sorts for system administrators who would like to provide access to remote users to both read and write local files without providing any remote execution priviledges. Functionally, it is a wrapper around the ssh suite of applications. It is typically used by creating a user whose shell is set to scponly. This user can neither login interactively nor execute commands remotely, but it can use scp and sftp to download and upload files to the computer, governed by the usual Unix file permissions.