Lynis is an auditing and hardening tool for Unix derivatives like Linux/BSD/Solaris. It scans systems to detect software and security issues. Besides security-related information, it will also scan for general system information, installed packages, and possible configuration mistakes. The software is aimed at assisting automated auditing, software patch management, and vulnerability and malware scanning of Unix-based systems.
Ultimate Boot CD is a collection of Freeware and Free Software tools for PC diagnostics and maintenance. Included are tools for BIOS editing, CPU and memory testing, boot management, data recovery, peripheral and system inventory, and hard drive partitioning, cloning, wiping, diagnostics, and low-level editing. All tools boot and run from the CD.
SystemRescueCd is a Linux system available from a bootable CDROM that provides an easy way to perform administrative tasks on your computer, such as creating and editing the partitions of the hard disk or backing up data. It contains a lot of system utilities (such as parted, partimage, and fstools), and basic programs (such as editors, midnight commander, and network tools). It also includes GParted, a Partition Magic clone that makes editing partitions easy with its graphical user interface. This CDROM aims to be very easy to use and accessible to everybody, and it also provides advanced personalization features.
INSERT (the Inside Security Rescue Toolkit) aims to be a multi-functional, multi-purpose disaster recovery and network analysis system. It boots from a credit card-sized CD-ROM and is basically a stripped-down version of Knoppix. It features good hardware detection, fluxbox, emelfm, links-hacked, ssh, tcpdump, nmap, chntpwd, and much more. It provides full read-write support for NTFS partitions (using ntfs-3g), and the ClamAV virus scanner (including a fairly recent signature database and a GUI). It provides partition handling with gParted and also has a network boot facility.
dstat is a versatile replacement for vmstat, iostat, netstat, nfsstat, and ifstat. It includes various counters (in separate plugins) and allows you to select and view all of your system resources instantly; you can, for example, compare disk usage in combination with interrupts from your IDE controller, or compare the network bandwidth numbers directly with the disk throughput (in the same interval).
GroundWork Monitor Community Edition can give you insight into your computing infrastructure, allowing you to see the current and historical states of all your computers: servers, desktops, and laptops, all of your network devices, all of your services (like TCP/IP and Web services), and all of your applications (like mail servers and database apps). You can choose to be alerted when something goes awry via pager, SMS, email, or phone, and even set up automatic restarts or fall-overs.
memtester is a user-space utility for testing the memory subsystem in a computer to determine if it is faulty. It does a good job of finding intermittent faults and non-deterministic faults. It has many tests to help catch borderline memory. memtester should compile and run on any 32- or 64-bit Unix or Unix-like system.