Preview: RootPrompt -- Nothing but Unix
RootPrompt -- Nothing but Unix
News and information for Unix Sysadmins
Block crackers with 3 locks to your SSH door (18 Oct 2010)
Security always requires a multi-layered scheme. SSH is a good example of this. Methods range from simple sshd configuration through the use of PAM to specify who can use SSH, to application of port-knocking techniques, or to hide the fact that SSH access even exists. Applying these techniques can make life much harder for possible intruders, who will have to go past three unusual barriers."Learn 3 ways of hardening SSH access to your system to block would-be crackers"
Bazaar: source control system (15 Oct 2010)
Bazaar is used to produce the Ubuntu Linux distribution, which is an enormous software project with thousands of components. If you're using a UNIX or Linux system, chances are that your distribution offers a pre-built Bazaar package. Bazaar is flexible enough to accommodate Subversion - a centralized system and Git - a decentralized system. This article introduces you to Bazaar's many appealing features."Intro to Bazaar, a great place to keep your code"
User space memory access from the Linux kernel (13 Oct 2010)
As the kernel and user space exist in different virtual address spaces, there are special considerations for moving data between them. Explore the ideas behind virtual address spaces and the kernel APIs for data movement to and from user space, and learn some of the other mapping techniques used to map memory."An introduction to Linux memory and user space APIs"
Techniques for migrating Perl to Python (11 Oct 2010)
Python programmers shouldn't get too smug. While many people agree that Python is designed in a way that makes it a highly readable language, there can still be problems with legacy, untested Python code too. Porting legacy Perl to Python can be a daunting task. In this article, learn some of the theory behind dealing with legacy code, including what not to do."Techniques for migrating legacy, untested Perl to Python"
New AIX 7 capabilities for virtualization (8 Oct 2010)
The IBM AIX operating system provides a highly scalable IT infrastructure for client workloads. Learn about the latest version, AIX 7.1, an open standards-based UNIX operating system, that includes significant new capabilities for virtualization, security features, availability features, and manageability."Learn about the latest version of AIX 7.1 - an open standards-based UNIX operating system"
Introduction to PowerHA (1 Sep 2010)
PowerHA for AIX is the new name for HACMP (High Availability Cluster Multiprocessing). HACMP is an application that makes system fault resilient and reduces downtime of applications. This article introduces PowerHA and provides a detailed explanation of how to configure a two node cluster. This document is very useful for understanding PowerHA and setting up a two node cluster."Get Power high availability by Configuring a PowerHA cluster" Introduction to PowerHA
Yeah - Learn Linux: Maintain the integrity of file (30 Aug 2010)
Learn how to check the integrity of your Linux filesystems, monitor free space, and fix simple problems. Use the material in this article to study for the Linux Professional Institute (LPI) 11 exam for Linux system administrator certification or just to check your filesystems and keep them in good working order, especially after a system crash or power loss. Today's world relies heavily on technology, and at times technology can fail us. That is why, unlike traditional methods of storage s
Live Kernel Patches with Ksplice (11 Aug 2010)
Ksplice applies kernel patches on-the-fly - no reboot required in a fraction of a second. Here's a hands-on guide to performing painless system updates. Learn how to patch a live kernel and give reboots the boot."Avoid reboots of your system with live Kernel updates using Ksplice" Live Kernel Patches with Ksplice
vi tips and tricks: Ten cool commands (2 Aug 2010)
Amaze your friends with cool vi tips and tricks that will improve the efficiency of your file editing. This article takes you through ten of the less well-known vi commands that should form part of any serious vi user's toolkit."Become a vi editing wizard with these 1 tips" vi tips and tricks: Ten cool commands
Understanding ZFS & ZFS ARC/L2ARC (26 Jul 2010)
Great article describing level one and two memory caching in zfs."L2ARC is a new layer between Disk and the cache (ARC) in main memory for ZFS. It uses dedicated storage devices to hold cached data. The main role of this cache is to boost the performance of random read workloads. The intended L2ARC devices include 1K/15K RPM disks like short-stroked disks, solid state disks (SSD), and other media with substantially faster read latency than disk." Understanding ZFS & ZFS ARC/L2ARC
Creates a whole new painting tool for GIMP (23 Jul 2010)
The GNU Image Manipulation Program (GIMP) is a robust application for editing and manipulating digital images. In this article, you will learn how to get started with the GIMP code, how to build the project from the Git repositories, and how to find your way around the code tree. And you will build an example application that creates a whole new painting tool for the program."Dive into the code base of the GNU Image Manipulation Program and add to it"
Gourmet Java technology for Android applications (21 Jul 2010)
Java language is the tool of choice for Android developers. The Android runtime uses its own virtual machine, Dalvik, which is not the usual Java virtual machine that most Java developers are used to. In this article you will learn advanced Java features and how they are implemented on Android. This includes features such as concurrency, networking, and database access."
Implement concurrency, networking, and database access in Android" http://www.ibm.com/developerworks/library/x-gourmetand
More powerful Python testing techniques (20 Jul 2010)
Look at how the leading Python testing frameworks provide robust auto-discovery of your application tests. Make sure your applications are written right the first time, and that they stay working through months and years of further tweaks and improvements.
Distributed data processing with Hadoop (19 Jul 2010)
In Part 1 learn to Install and configure a simple cluster and discover ways to monitor and manage Hadoop using its core Web interfaces. In Part 2 Install configure a multinode cluster and dig into the management aspects of Hadoop.
"How to use Hadoop in a single-node and multinode cluster" http://www.ibm.com/developerworks/linux/library/l-hadoop-1/index.html?ca=dgr-lnxw1HadoopP1dth-LX
Creating mobile Web applications with HTML5 (15 Jul 2010)
In this five-part series, you will take a closer look at several new technologies that are part of HTML5, that can have a huge impact on mobile Web application development.
Part 1: Combine HTML5, geolocation APIs, and Web services to create mobile mashups
Part 2: Unlock local storage for mobile Web applications with HTML5
Part 3: Make mobile Web applications work offline with HTML5
Part 4: Using Web Workers to speed up your mobile Web applications
Part 5: Develop new visual UI features in
Anatomy of the Linux virtual file system switch or donate; car & computer technology (13 Jul 2010)
With the Linux virtual file system switch (VFS), you can create file systems on a variety of devices, from traditional disk, USB flash drives, memory, and other storage devices. You can even embed a file system within the context of another file system. Discover what makes the VFS so powerful, and learn its major interfaces and processes. Understanding the dynamics of such a system will benefit you in the long run. In today's ever growing technological era you must try and stay up to date
UNIX network performance analysis (12 Jul 2010)
Do you know what to do when the performance of your UNIX network and the speed at which you can transfer files or connect to services suddenly comes to a stop? How do you diagnose the issues and work out where in your network the problems lie? This article looks at some quick methods for finding and identifying performance issues and the steps to start resolving them.
Speak UNIX fluently with the best tools available (11 Jul 2010)
Much like a vernacular, the universe of UNIX tools changes almost perpetually. New tools crop up frequently, while others are eternally modernized and adapted to suit emerging best practices. To speak UNIX fluently, you have to keep up with whats New and good.
Worry-free Linux power-downs with Anacron (10 Jul 2010)
Linux ordinarily uses Cron to automatically perform routine system maintenance on desktop or laptop computers, however not running Cron routinely can result in monstrously large log files and other problems. You can offload most or all of your usual daily and longer-interval Cron jobs onto Anacron enabling your computer to run regular maintenance jobs whenever the computer is powered on, even if those times are unpredictable.
Guide to porting from Solaris to Linux on POWER (8 Jul 2010)
Accelerate your porting efforts by following this six-step guide to porting from Solaris to Linux on POWER. Learn the differences between Solaris and Linux on POWER that you commonly encounter during a port. Also learn about tools for performance analysis and software packaging for Linux on POWER.
HOW TO: Teach your old Mutt some new tricks (1 Jul 2010)
Was always a pine fan before I went to Gmail. "Many geeks ditch the heavy graphical or web-based mail clients for a lean, mean solution: mutt. Mutt's a character-based Mail User Agent (MUA) that snaps to your every command. It also provides powerful features for customization, organizing large volumes of email (especially from mailing lists), and interfacing to other applications." HOW TO: Teach your old Mutt some new tricks
Unix turns 40 (8 Jun 2009)
Nice retrospective by computer world."After batting around some ideas for a new system, Thompson wrote the first version of Unix, which the pair would continue to develop over the next several years with the help of colleagues Doug McIlroy, Joe Ossanna and Rudd Canaday. Some of the principles of Multics were carried over into their new operating system, but the beauty of Unix then (if not now) lay in its less-is-more philosophy." Unix turns 4
Using PHP directly from the command line on Linux (5 Jun 2009)
Learn how to better integrate scripts with command-line tools. Examine using shell_exec(), exec(), passthru(), and system(); safely passing information to the command line; and safely retrieving information from it. If you are looking to monetize from a website without the PHP knowledge, you can always try an online membership website builder.
See how to integrate closely with underlying shell commands and folding any return values into your interfaces and processes.
Anatomy of a Linux hypervisor (5 Jun 2009)
The battleground has shifted from the Operating System to the hypervisor, and Linux has a clear role to play. One of the most important modern innovations of Linux is its transformation into a hypervisor. Learn about KVM and Lguest and why the most important modern innovations of Linux is its transformation into a hypervisor
Boost Linux performance on old hardware (1 Jun 2009)
The ideas in this article may help you breathe life (and some additional security) into your old machines and make better use of Linux on aging hardware. A lack of physical memory can severely hamper Linux performance. Llearn how to accurately measure the amount of memory your Linux system uses. You also get practical advice on reducing your memory requirements using an Ubuntu system as an example.
Comparing UNIX inovation (29 May 2009)
This article compares and contrasts some of the innovations of the latest releases of AIX 6.1, Solaris 1, and HP-UX. Learn the differences on how to work with certain tasks, such as networking and performance tuning. Also, see at a high level some of the virtualization differences among these big three. You decide what you prefer best.
Modify xorg.conf for better performanc (26 May 2009)
Some nice info in this."Most of the time, your screen's capabilities should be identified using something called EDID - Extended Display Identification Data. This is a chunk of information sent from your display to your graphics card, and normally contains information such as your screen's model and manufacturer, resolution timings and display size. X then uses this data to create appropriate resolutions and bit depths that make optimal use of your hardware." Modify xorg.conf for better per
Puppet and Subversion in Fifteen Minutes (25 May 2009)
As data centers grow in both size and complexity, the ability to manage the configuration of each and every server from a central location becomes increasingly important. Two popular Open Source configuration management solutions exist: cfengine and Puppet."Puppet is written in Ruby, is easily installed, and as we will see, can be setup and taken live in less than fifteen minutes!" Puppet + subversion in 15 minutes
Build your first Android application: Create anything from wedding invitations designer to caloric calculator (19 May 2009)
Android, a complete operating environment based upon the Linux V2.6 kernel, promises to be a market-moving open source platform that will be useful well beyond cell phones. In this article, learn about the Android platform and how it can be used for mobile and nonmobile applications, then build your first Android application. This simple first app you build will get you started quickly, but believe me, you'll want to do more after that. Applications are quickly becoming the thing to have.
Who has better virtualization (19 May 2009)
Why is virtualization so important? The short answer is that virtualization enables businesses to lower their technology Total Cost of Ownership (TCO), while increasing their Return on Investment (ROI). What do the top UNIX vendors have to offer with respect to virtualization? Find out what virtualization is more scalable. Here's a look at HP's Virtual Server Environment (VSE), Sun's xVM, and IBM's PowerVM.
Cheap, Readable, Low-Power Displays (14 May 2009)
I want an ebook reader like device. But am way to cheap to get anything I have seen on the market. If the Kindle was $15 I think I would be carrying one around. Well if there was more of an electronic version discount for the books at least.""Effectively what [Pixel Qi is] doing is creating a hybrid display that combines the best of E Ink and regular LCDs," says Robert Barry, director of business development for Team Research, a company that makes an e-book reader called the Astak Mentor
MySQL Clustering in a Sandbox (13 May 2009)
"MySQL's clustering storage engine is a unique take on database clustering, unlike Oracle's or Microsoft SQL Servers solutions. As with those, it has its strengths and weaknesses, so you'll of course need to test, test, and test some more before you can decide if the technology is right for your application, and organization. New features that are in development include the ability to add nodes while the cluster is up and running, storing data and index information on disk, and much more.
MOC: Text based audio player (12 May 2009)
Who needs GUIs?"Based on ncurses, MOC (music on console) is a popular, text-based audio player which can play various audio formats, including Ogg Vorbis, FLAC, MP3, MP4, WMA and WAV. The release I'm going to talk about in this article is 2.5.-alpha3, as it comes with Debian Lenny." MOC: Text based audio player
Scripting the Vim editor with Vmscript (11 May 2009)
Vimscript is a mechanism for reshaping and extending the Vim editor. Scripting allows you to create new tools, simplify common tasks, and even redesign and replace existing editor features. This article introduces the fundamental components of the Vimscript programming language: values, variables, expressions, statements, functions, and commands. These features are demonstrated and explained through a series of simple examples.
VirtualBSD Review--Inside and Out (7 May 2009)
I am thinking that this is basically a toy. I may be wrong though may be some good use that it could be put to. It is interesting though."The only difference is that, unlike Kandor, VirtualBSD is trapped in VMware not in a bottle. You can't install it directly to your computer as an independent OS at this point. Nor can you run it as a Live CD to get a taste of it without installing anything. VirtualBSD exists solely as a VMware appliance right now." VirtualBSD Review--Inside and Out