TrinityOS is a step-by-step, example-driven HOWTO on building a very functional Linux box with strong security in mind. TrinityOS is well known for its strong packet firewall ruleset, Chrooted and Split DNS (v9 and v8), secured Sendmail (8.x), Linux PPTP, Serial consoles and Reverse TELNET, DHCPd, SSHd, UPSes, system performance tuning, the automated TrinityOS-Security implementation scripts, and much more.
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.
PIKT is cross-categorical, multi-purpose software for monitoring and configuring computer systems, administering networks, organizing system security, and much more. PIKT is intended primarily for system monitoring, and secondarily for configuration management, but its versatility and extensibility evoke many other wide-ranging uses. PIKT consists of a sophisticated, feature-rich file preprocessor; an innovative scripting language with unique labor-saving features; a flexible, centrally directed process scheduler; a customizing file installer; a collection of powerful command-line extensions; and other useful tools.
Finnix is a small, self-contained, bootable Linux CD distribution ("LiveCD") for system administrators, based on Debian testing. You can use it to mount and manipulate hard drives and partitions, monitor networks, rebuild boot records, install other operating systems, and much more.
The IP Masquerade HOWTO is the document that contains instructions on understanding, configuring, and troubleshooting NAT or Network Address Translation for Linux. It covers topics such as IPTABLES, PORTFW, IPCHAINS, IPFWADM, stronger packet firewalls, multiple network segments, and configuring many client operating systems. It also has an extensive FAQ and troubleshooting section.
Virtual Appliances are nano-sized virtual machines for deploying instant infrastructure and applications. They are Ubuntu Server Edition 8.04 based and available for VMware, QEMU, KVM, Parallels, Xen, Virtual Iron, Virtural PC, and Virtual Server. Available Virtual Appliances are a LAMP Server, LAPP Server, Apache Tomcat Server, and Cacti Virtual Appliance. These are the smallest, most functional, and easiest to use Virtual Appliances available. They are certified for use on VMware and Parallels.
Andutteye is a systems management platform that automates enterprise data centers and keeps them running. It contains different modules that targets different tasks of systems management. From a single point of operations you can monitor, manage, and execute all ranges of tasks needed for centralized systems management.
The GNOME NetworkManager is a set of co-operative tools that make networking simple and straightforward. Whether wireless or wired, NetworkManager allows you to quickly move from one network to another: once a network has been configured and joined once, it can be detected and re-joined automatically at a later date. It was designed to auto-detect as much information as possible, seamlessly switches connections when necessary, and provides immediate feedback of the network state to users and applications.