di is a disk information utility that displays everything that df does and more. It features the ability to display your disk usage in whatever format you prefer. It also checks the user and group quotas, so that the user sees the space available for their use, not the system wide disk space. It is designed to be highly portable across many platforms and is great for heterogenous networks.
MultiTail lets you view one or multiple files like the original tail program. The difference is that it creates multiple windows on your console (with ncurses). Merging of 2 or more log files is possible. It can also use colors while displaying the log files (through regular expressions) for faster recognition of what is important. It can also filter lines (again with regular expressions). It has interactive menus for editing given regular expressions and deleting and adding windows. One can also have windows with the output of shell scripts and other software. When viewing the output of external software, MultiTail can mimic the functionality of tools like 'watch'.
CoralReef is a comprehensive software suite developed by CAIDA for collecting and analyzing data from passive Internet traffic monitors in real time or from trace files. The package also includes programming APIs for C and Perl, and applications for capture, analysis, and Web report generation.
The libstatgrab library provides an easy-to-use interface for accessing system statistics and information. Available statistics include CPU, Load, Memory, Swap, Disk I/O, and Network I/O. It was developed to work on Linux, FreeBSD, and Solaris. The package also includes two tools: saidar provides a curses-based interface for viewing live system statistics, and statgrab is a sysctl-like interface to the statistics.
PHREL is a per host rate limiter. It will track the rate of incoming traffic on a server and insert a chain into iptables when a configured threshold is crossed. The inserted chain may either rate limit or block the offending host for a period of time. The inserted chain is automatically removed when the offending host's traffic levels return to normal. PHREL is particularly well suited to protecting nameservers (DNS) from random hosts that flood requests, and to preventing SSH brute force login attempts.
Trojan scan is a simple shell script that allows for simple but relatively effective checking for trojans, rootkits and other malware that may be using your server and network for unwanted (and possibly illegal) purposes. It works by listing all processes that use the Internet with the lsof command (using -Pni flags). This list is then transformed into signatures in the form of process_name:port_number:user. These signatures then are matched against the allowed process defined in the configuration. If any signatures of running processes are found that do not match the allowed signatures, an email report is sent including ps, ls, and optional lsof output.