Linux is a clone of the Unix kernel, written from scratch by Linus Torvalds with assistance from a loosely-knit team of hackers across the Net. It aims towards POSIX and Single UNIX Specification compliance. It has all the features you would expect in a modern fully-fledged Unix kernel, including true multitasking, virtual memory, shared libraries, demand loading, shared copy-on-write executables, proper memory management, and TCP/IP networking.
Clonezilla is a partition or disk cloning tool similar to Symantec Ghost. It saves and restores only blocks in use on the hard drive if the file system is supported. For unsupported file systems, dd is used instead. It has been used to clone a 5 GB system to 40 clients in about 10 minutes.
BalanceNG is a modern, IPv6 capable software IP load balancing solution. It is small, fast, and easy to use and set up. It offers session persistence, different distribution methods (Round Robin, Random, Weighted Random, Least Session, Least Bandwidth, Hash, Agent, and Randomized Agent) and a customizable UDP health check agent in source code. It supports VRRP to set up high availability configurations on multiple nodes. It supports SNMP, integrating the BALANCENG-MIB with Net-SNMPD. It implements a very fast in-memory IP-to-location database, allowing powerful location-based server load-balancing.
LiVES is a simple to use yet powerful video effects, editing, conversion, and playback system aimed at the digital video artist and VJ. It runs under Linux, BSD, Mac OS X/Darwin, IRIX, and openMosix. It is frame and sample accurate, can handle almost all types of video, and is fully extendable through plugins and the included plugin builder tool. It can also be controlled remotely using OSC.
Diskless Remote Boot in Linux (DRBL) provides a diskless or systemless environment for client machines. It works on Debian, Mandriva, Red Hat, Fedora, and SuSE. Unlike LTSP, it uses distributed hardware resources and makes it possible for clients to fully access local hardware. It also includes Clonezilla, a partitioning and disk cloning utility similar to Symantec Ghost.
The Advanced Bash Scripting Guide is both a reference and a tutorial on shell scripting. This comprehensive book, the equivalent of 1,032 print pages, covers almost every aspect of shell scripting. It contains 382 profusely commented illustrative examples, a number of tables, and a cross-linked index/glossary. Not just a shell scripting tutorial, this book also provides an introduction to basic programming techniques, such as sorting and recursion. Included scripts are the Game of Life, a Perquackey variant, a Morse code trainer, and an implementation of the Gronsfeld Cipher. This book is suited for both individual study and classroom use. It covers Bash, up to and including version 4.2. Note that users of miniaturized single-board computers running Linux, such as the Raspberry Pi and the Beagle Bone, would find this Guide useful for learning and running Bash scripts to explore and expand the capabilities of these small, but powerful machines.
The Parted Magic OS employs core programs from GParted and Parted to handle partitioning tasks with ease, while featuring other useful programs including Partition Image, TestDisk, fdisk, sfdisk, dd, and ddrescue and an excellent set of documentation to benefit the user. An extensive collection of fileystem tools are also included, and the following filesystems are supported: ext2, ext3, ext4, FAT16, FAT32, HFS, HFS+, JFS, Linux-swap, NTFS, ReiserRS, reiser4, and XFS. It loads completely to system memory and requires at least 256MB of RAM to operate.
syslog-ng is a syslogd replacement for a wide variety of UNIX systems that supports IPv6 and is capable of transferring log messages reliably using TCP and SSL and filtering the content of messages using regular expressions. Both RFC3164 and RFC5424 style messages are handled, but more esoteric formats like BSD process accounting logs are supported too. Apart from regular text files, it supports storing messages into SQL and MongoDB databases, and forward messages to local processes via pipes or UNIX domain sockets. This makes syslog-ng ideal as an integration platform. syslog-ng supports extracting structured information from the traditionally text based syslog via csv-parser(), db-parser(), and patterndb. Tag based classification, rewriting messages, and outputting messages in JSON is also possible. This makes syslog-ng ideal for preprocessing events for further analysis, be that home-grown scripts or SIEM systems. syslog-ng scales well on today's multi processor and multi-core systems: reaching 1,000,000 messages per second is a reality for the simplest use cases.
The sysstat package contains the sar, sadf, iostat, nfsiostat, cifsiostat, mpstat, and pidstat commands for Linux. The sar command collects and reports system activity information. The statistics reported by sar concern I/O transfer rates, paging activity, process-related activites, interrupts, network activity, memory and swap space utilization, CPU utilization, kernel activities, and TTY statistics, among others. The sadf command may be used to display data collected by sar in various formats. The iostat command reports CPU statistics and I/O statistics for tty devices and disks. The pidstat command reports statistics for Linux processes. The mpstat command reports global and per-processor statistics. The nfsiostat command reports I/O statistics for network filesystems. The cifsiostat command reports I/O statistics for CIFS filesystems.