developerWorks : New to Linux programming and Linux system administration In the simplest terms, Linux is an operating system. It was created in October 1991 by a University of Helsinki student named Linus Torvalds (Linux stands for Linus's UNIX). Linux itself is actually just the kernel; it implements multitasking and multiuser functionality, manages hardware, allocates memory, and enables applications to run. The average user will never be interested enough in any operating system to want to know about things like kernel internals. Only the truly dedicated -- those who have no personal lives, or those who are being paid to do this kind of work -- are going to want to explore these intricacies. But even if you never descend to the giddy depths of kernel hacking yourself, it is reassuring to know that you can easily hire a contractor or firm to do this work for you; to commission such modifications for a proprietary system is very often a more difficult and more costly undertaking.
How To Look Like A UNIX Guru Terence Parr Last updated: August 30, 2006 Translations: UNIX is an extremely popular platform for deploying server software partly because of its security and stability, but also because it has a rich set of command line and scripting tools. Programmers use these tools for manipulating the file system, processing log files, and generally automating as much as possible. If you want to be a serious server developer, you will need to have a certain facility with a number of UNIX tools; about 15. This lecture takes you through the basic commands and then shows you how to combine them in simple patterns or idioms to provide sophisticated functionality like histogramming. [By the way, this page gets a lot of attention on the net and unfortunately I get mail from lots of people that have better solutions or stuff I should add. Everything is a stream The first thing you need to know is that UNIX is based upon the idea of a stream. $ ls > /dev/null # ignore output of ls $ ls -l | grep Aug | wc -l cd
Home - GitHub Learn Linux, 101: A roadmap for LPIC-1 About this series This series of articles helps you learn Linux system administration tasks. The topics mirror those of the Linux Professional Institute Certification (LPIC) level 1 (LPIC-1) exams. You can use the articles to prepare for certification, or just to learn about Linux. There are two exams for LPIC-1 certification: exam 101 and exam 102, and you must pass both to attain LPIC-1 certification. The material in these articles corresponds to the April 2009 objectives for exam 101 and exam 102 You should always refer to the objectives for the definitive requirements. This roadmap is in progress; as we complete articles, we add them to the roadmap. Note: New material will be added over the coming months as it becomes available. Exam 101 Exam 101 - Topic 101: System architecture Where are the articles? Back to top Exam 101 - Topic 102: Linux installation and package management Exam 101 - Topic 103: GNU and UNIX commands Where are the articles? Exam 102 Where are the articles?
How To Look Like A UNIX Guru Terence Parr Last updated: August 30, 2006 Translations: UNIX is an extremely popular platform for deploying server software partly because of its security and stability, but also because it has a rich set of command line and scripting tools. Programmers use these tools for manipulating the file system, processing log files, and generally automating as much as possible. If you want to be a serious server developer, you will need to have a certain facility with a number of UNIX tools; about 15. This lecture takes you through the basic commands and then shows you how to combine them in simple patterns or idioms to provide sophisticated functionality like histogramming. [By the way, this page gets a lot of attention on the net and unfortunately I get mail from lots of people that have better solutions or stuff I should add. Everything is a stream The first thing you need to know is that UNIX is based upon the idea of a stream . $ ls > /dev/null # ignore output of ls $ ls -l | grep Aug | wc -l cd
Unknown Bash Tips and Tricks For Linux Familiarity breeds ennui, and even though Bash is the default Linux command shell used daily by hordes of contented users, it contains a wealth of interesting and useful features that don't get much attention. Today we shall learn about Bash builtins and killing potential. Bash Builtins Bash has a bunch of built-in commands, and some of them are stripped-down versions of their external GNU coreutils cousins. Bash aliases Bash keywords Bash functions Bash builtins Scripts and executable programs that are in your PATH So when you run echo, kill, printf, pwd, or test most likely you're using the Bash builtins rather than the GNU coreutils commands. $ command -V echo echo is a shell builtin $ command -V ping ping is /bin/ping The Bash builtins do not have man pages, but they do have a backwards help builtin command that displays syntax and options: $ help echo echo: echo [-neE] [arg ...] The type command looks a lot like the command builtin, but it does more: $ type -t time keyword Bash Functions
cURL - Tutorial cURL Docs Tutorial HTTP Scripting 1.1 Background1.2 The HTTP Protocol1.3 See the Protocol1.4 See the Timing1.5 See the Response 2.1 Spec2.2 Host2.3 Port number2.4 User name and password2.5 Path part Fetch a page HTML forms 4.1 Forms explained4.2 GET4.3 POST4.4 File Upload POST4.5 Hidden Fields4.6 Figure Out What A POST Looks Like HTTP upload HTTP Authentication 6.1 Basic Authentication6.2 Other Authentication6.3 Proxy Authentication6.4 Hiding credentials More HTTP Headers 7.1 Referer7.2 User Agent Redirects 8.1 Location header8.2 Other redirects Cookies 9.1 Cookie Basics9.2 Cookie options 10.1 HTTPS is HTTP secure10.2 Certificates Custom Request Elements 11.1 Modify method and headers11.2 More on changed methods Web Login 12.1 Some login tricks Debug 13.1 Some debug tricks References 14.1 Standards14.2 Sites 1. 1.1 Background This document assumes that you're familiar with HTML and general networking. Curl is not written to do everything for you. 1.2 The HTTP Protocol The client, curl, sends a HTTP request. or 3.
Cool, but obscure unix tools :: KKovacs Just a list of 20 (now 28) tools for the command line. Some are little-known, some are just too useful to miss, some are pure obscure -- I hope you find something useful that you weren't aware of yet! Use your operating system's package manager to install most of them. (Thanks for the tips, everybody!) dstat & sar iostat, vmstat, ifstat and much more in one. slurm Visualizes network interface traffic over time. vim & emacs The real programmers' editors. screen, dtach, tmux, byobu Keep your terminal sessions alive. multitail See your log files in separate windows. tpp Presentation ("PowerPoint") tool for terminal. xargs & parallel Executes tasks from input (even multithread). duplicity & rsyncrypto Encrypting backup tools. nethack & slash'em Still the most complex game on the planet. lftp Does FTPS. ack, ag (silver searcher), pt A better grep for source code. calcurse & remind + wyrd Calendar systems. newsbeuter & rsstail Command line RSS readers. powertop Helps conserve power on Linux. tig A console UI for git. mtr
Migrating data Introduction Migrating or moving data is a common task. Whether it is copying data across the network to a new filesystem, or copying logical volumes within the same volume group or to a different volume group or maybe just creating a backup of a filesystem. The reasons for moving or copying data could be for performance issues, or general growth of data where there is not enough space in its current environment. Back to top Using tar and cp to copy data to a new filesystem When applying updates to an application filesystem, a backup would be taken first, most probably to tape. # df -g … /dev/fslv00 1.00 0.03 97% 22 1% /opt/pluto Let's look at three ways we could copy the application files across to another filesystem, using cp, tar, and cplv. First, the backup (copied) filesystem needs to be created. # crfs -v jfs2 -g rootvg -m /opt/pluto_bak -A yes -p rw -a agblksize=40 96 -a size=1G File system created successfully. 524068 kilobytes total disk space. For /opt/pluto_bak, we have: # cd .. to
UNIX tips: Learn 10 good UNIX usage habits Break bad UNIX usage patterns Michael StutzPublished on December 12, 2006 When you use a system often, you tend to fall into set usage patterns. Sometimes, you do not start the habit of doing things in the best possible way. Sometimes, you even pick up bad practices that lead to clutter and clumsiness. One of the best ways to correct such inadequacies is to conscientiously pick up good habits that counteract them. Adopt 10 good habits Ten good habits to adopt are: Make directory trees in a single swipe Listing 1 illustrates one of the most common bad UNIX habits around: defining directory trees one at a time. Listing 1. It is so much quicker to use the -p option to mkdir and make all parent directories along with their children in a single command. Listing 2. You can use this option to make entire complex directory trees, which are great to use inside scripts; not just simple hierarchies. Listing 3. Change the path; do not move the archive Listing 4. Listing 5. Listing 6. Listing 7.
Puppet Labs: IT Automation Software for System Administrators