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Traversing Red Hat Enterprise Linux 5 on System p So you've been the AIX guru on your team for years now and your bosses have determined that they want to try Linux on System p. You can fight the change, or you can embrace it and learn Linux, if not learn to love it. The purpose of this article is to introduce Linux to AIX administrators. It will show you what you need to know to make the transition to Linux simpler. It will also show you the equivalent commands to perform specific tasks and also discusses process management, filesystem management, how to peruse systems information, install packages, and other important bits of information that you as the systems administrator will need to know. While you will not become an expert at Linux from this article, this should give you a good head start in what you need to know. Lazy Linux: 10 essential tricks for admins Learn these 10 tricks and you'll be the most powerful Linux systems administrator in the universe...well, maybe not the universe, but you will need these tips to play in the big leagues. Learn about SSH tunnels, VNC, password recovery, console spying, and more. Examples accompany each trick, so you can duplicate them on your own systems. Running Informix Dynamic Server on Linux in Xen hypervisor Can Informix Dynamic Server (IDS) run on Linux in Xen hypervisor virtual machines (VM)? Is all OS-specific functionality of IDS usable in a Xen VM? This article is a detailed summary of first experiences with running IDS for Linux in a Xen managed virtual machine. In this article, learn more about the benefits of Xen hypervisor and see how it works. Follow step-by-step guidelines to set up an actual test system, including the Xen virtualization layer. Finally, learn about the results of tests that the authors ran on their IDS environments. Anatomy of Linux loadable kernel modules Linux loadable kernel modules, introduced in version 1.2 of the kernel, are one of the most important innovations in the Linux kernel. They provide a kernel that is both scalable and dynamic. Discover the ideas behind loadable modules, and learn how these independent objects dynamically become part of the Linux kernel. Integrate encryption into Google Calendar with Firefox extensions Today's Web applications provide many benefits for online storage, access, and collaboration. Although some applications offer encryption of user data, most do not. This article provides tools and code needed to add basic encryption support for user data in one of the most popular online calendar applications. Building on the incredible flexibility of Firefox extensions and the Gnu Privacy Guard, this article shows you how to store only encrypted event descriptions in Google's Calendar application, while displaying a plain text version to anyone with the appropriate decryption keys. Automate backups on Linux The loss of critical data can prove devastating. Still, millions of professionals ignore backing up their data. While individual reasons vary, one of the most common explanations is that performing routine backups can be a real chore. Because machines excel at mundane and repetitive tasks, the key to reducing the inherent drudgery and the natural human tendency for procrastination, is to automate the backup process. Common threads: Awk by example, Part 1 Awk is a very nice language with a very strange name. In this first article of a three-part series, Daniel Robbins will quickly get your awk programming skills up to speed. As the series progresses, more advanced topics will be covered, culminating with an advanced real-world awk application demo. Migrate device control applications from Windows to Linux Ease the pain of migrating device control applications from Microsoft Windows to Linux by understanding how device control works in both operating systems. The authors outline these differences and give you a C/C++ migration sample. Core partners, Part 4: Managing the PlayStation 3 Wi-Fi network Terra Soft Solutions IT Manager Aaron Johnson shows you, step-by-step, how to configure and encrypt the built-in Wi-Fi network that comes with the Cell Broadband Engine(TM)-based Sony PlayStation 3. And, as a little bonus, get 16 quick steps that explain how to switch from a wireless network back to a wired network on the PS3. Anatomy of Linux journaling file systems In recent history, journaling file systems were viewed as an oddity and thought of primarily in terms of research. But today, a journaling file system (ext3) is the default in Linux. Discover the ideas behind journaling file systems, and learn how they provide better integrity in the face of a power failure or system crash. Learn about the various journaling file systems in use today, and peek into the next generation of journaling file systems. Porting applications to Linux for System z Server consolidation based on Linux for IBM System z offers advantages, but moving existing applications requires some specialized knowledge. In this article, get general advice on how to organize your porting project, including technical details on mainframe virtualization, byte-ordering, and address calculation specific to System z. This article also covers how development tools (compiler, linker, debugger) are supported on System z, and introduces IBM's free-of-charge Migration Kit for Solaris OS to Linux. Anatomy of Linux flash file systems You've probably heard of Journaling Flash File System (JFFS) and Yet Another Flash File System (YAFFS), but do you know what it means to have a file system that assumes an underlying flash device? This article introduces you to flash file systems for Linux, and explores how they care for their underlying consumable devices (flash parts) through wear leveling, and identifies the various flash file systems available along with their fundamental designs. Manage widget geometry in PyGTK Several container widgets exist in GTK+, and with the toolkit's API, you can create user-defined containers. This API is also exposed to PyGTK. In this article, learn how to create a "weighted-table" container in PyGTK. The implementation introduces you to the basic model of GTK+ geometry management and gives you a feel for what to consider and expect when implementing container widgets. IBM open collaboration client solution: An overview Learn what's involved when introducing a Linux® client pilot in your organization, including planning for business and IT requirements, architecture decisions, risks, and understanding how IBM's open collaboration client is used to implement this desktop of the future, today. IBM open collaboration client solution: Organizational planning and user segmentation for desktop migration Learn the steps involved in migrating your environment to that of a Linux® client, including organizational planning and user segmentation. Based on customer experiences, this article offers a comprehensive guide to planning and executing your migration while minimizing disruption to your users. IBM open collaboration client solution: Technical planning Learn the steps involved in migrating your environment to that of a Linux client, including technical planning. Based on customer experiences, this article offers a comprehensive guide to planning and executing your migration while minimizing disruption to your users. Install and boot Linux on BladeCenter S from an attached disk The IBM BladeCenter S chassis is the first IBM BladeCenter to integrate server and storage. In this article, learn how to install SUSE Linux 10 on the blade's attached disk and then how to boot the blade server from the attached disk. The article also covers how to check the storage and blade status, how to map the disk to the blade, how to configure an SAS disk as the boot media, how to install the operating system on the attached disk, and how to handle the most common installation error. Migrating to ext4 Ext4 is the latest in a long line of Linux file systems, and it's likely to be as important and popular as its predecessors. As a Linux system administrator, you should be aware of the advantages, disadvantages, and basic steps for migrating to ext4. This article explains when to adopt ext4, how to adapt traditional file system maintenance tool usage to ext4, and how to get the most out of the file system. Anatomy of Security-Enhanced Linux (SELinux) Linux has been described as one of the most secure operating systems available, but the National Security Agency (NSA) has taken Linux to the next level with the introduction of Security-Enhanced Linux (SELinux). SELinux takes the existing GNU/Linux operating system and extends it with kernel and user-space modifications to make it bullet-proof. If you're running a 2.6 kernel today, you might be surprised to know that you're using SELinux right now! This article explores the ideas behind SELinux and how it's implemented. IBM open collaboration client solution: Migrating applications to the Linux desktop Have you wanted to port your infrastructure and business line applications to a Linux desktop environment, but been deterred by the need to access critical Microsoft Windows or legacy applications? Finding a way to support these critical business line applications is crucial when considering the move to Linux. This article highlights the various tools that let you access these applications from Linux desktops. Configuring WebSphere Message Broker V6.1 on z/Linux You have a number of options when configuring WebSphere Message Broker on z/Linux, including support for 64-bit applications in order to access DB2 and WebSphere MQ data on z/OS, use of IFL processors to lower the cost of ownership for WebSphere Message Broker, and use of HiperSockets for fast communication using TCP/IP-based protocols. This article has the details. Cell/B.E. SDK 3.0 tools, Part 1: Using performance tools This introductory tutorial, designed as a companion for the IBM SDK for Multicore Acceleration, Version 3.0 (otherwise known as the Cell Broadband Engine(R) SDK), teaches you how to use five performance tools that reside in the SDK 3.0: OProfile, Cell Performance Counter, Performance Debugging Tool, the PDT Trace Reader, and FDPR-Pro. The Visual Performance Analyzer, available separately, is also highlighted. LPI exam 301 prep, Topic 306: Capacity planning In this tutorial, Sean Walberg helps you prepare to take the Linux Professional Institute Senior Level Linux Professional (LPIC-3) exam. In this last in a series of six tutorials, Sean walks you through monitoring your system resources, troubleshooting resource problems, and analyzing system capacity. Anatomy of real-time Linux architectures It's not that Linux isn't fast or efficient, but in some cases fast just isn't good enough. What's needed instead is the ability to deterministically meet scheduling deadlines with specific tolerances. Discover the various real-time Linux alternatives and how they achieve real time -- from the early architectures that mimic virtualization solutions to the options available today in the standard 2.6 kernel. LPI exam 301 prep, Topic 305: Integration and migration In this tutorial, Sean Walberg helps you prepare to take the Linux Professional Institute Senior Level Linux Professional (LPIC-3) exam. In this fifth in a series of six tutorials, Sean walks you through integrating LDAP with your system's logins and applications. He also details the procedure to integrate your server into a foreign Microsoft Active Directory. Linux development on the PlayStation 3, Part 3: Slimming down X11 with tiny tools The Sony PlayStation 3 (PS3) runs Linux, but getting it to run well requires some tweaking. In the third and final article of this series on PS3 Linux, Peter Seebach talks about ways to get X11 slimmed down to fit on a smaller memory budget. Discover tput One of the strongest assets UNIX has is the ability to make shell scripts to ease users' lives. These scripts can range from simple one-liners to several thousand lines. Many times, shell scripts evolve into menu-based scripts, and the scripter wants to display more to users than simply scrolling text. Other times, a simple line or two of output are displayed to users, and the shell scripter wants to put emphasis on a warning message. Linux development on the PlayStation 3, Part 2: Working with memory The Sony PlayStation 3 (PS3) runs Linux, but getting it to run well requires some tweaking. In this article, the second in a series, Peter Seebach takes a look at where all the memory goes and how to reclaim it. Performance tradeoffs of TCP Selective Acknowledgment Selective acknowledgment (SACK) is an optional feature of TCP that is necessary to effectively use all of the available bandwidth of some networks. While SACK is good for throughput, processing this type of acknowledgment has proven to be CPU intensive for the TCP sender. This weakness can be exploited by a malicious peer even under commodity network conditions. This article presents experimental measurements that characterize the extent of the problem within the Linux TCP stack. SACK is enabled by default on most distributions. LPI exam 301 prep, Topic 304: Usage In this tutorial, Sean Walberg helps you prepare to take the Linux Professional Institute Senior Level Linux Professional (LPIC-3) exam. In this fourth in a series of six tutorials, Sean walks you through searching your LDAP tree and using the command-line tools. You'll also learn how to set up Microsoft Outlook to query your LDAP tree. Monitor mainframe sessions remotely Users access z/OS mainframes using a 3270 terminal emulator. In this article, learn how to build a simple shell script for UNIX or Linux that gives you a second terminal emulator to view everything a mainframe user is doing in real time. Linux development on the PlayStation 3, Part 1: More than a toy The Sony PlayStation 3 (PS3) runs Linux, but getting it to run well requires some tweaking. In this article, first in a series, Peter Seebach introduces the features and benefits of PS3 Linux, and explains some of the issues that might benefit from a bit of tweaking. LPI exam 301 prep, Topic 303: Configuration In this tutorial, Sean Walberg helps you prepare to take the Linux Professional Institute Senior Level Linux Professional (LPIC-3) exam. In this third in a series of six tutorials, Sean walks you through configuring a Lightweight Directory Access Protocol (LDAP) server, including access control, security, and performance. By the end of this tutorial, you'll know about LDAP server configuration. Changing UIDs and GIDs It's important to know what happens to file ownership in AIX once you make a UID or GID change. If you don't understand the results of altering a UID or GID, you could cause serious issues to your server and environment. Multipath storage with Xen and DS4800 As the Xen open source hypervisor gains traction in many enterprises for production deployment, you may need to provide fully redundant storage to the Xen environment from the host adapter all the way down to the hard drives. In this article, learn how to use Red Hat Enterprise Linux 5.1 to set up Xen and multipath storage access to the IBM System Storage DS4800. Desktop development for the OLPC laptop The XO laptop (of the One-Laptop-Per-Child initiative) is an inexpensive laptop project intended to help educate children around the world. The laptop includes many innovations, such as a novel, inexpensive, and durable hardware design and the use of GNU/Linux as the underlying operating system. The XO also includes an application environment written in Python with a human interface called Sugar, accessible to everyone (including kids). This article is excerpted from the developerWorks tutorial "Application development for the OLPC laptop," which takes a look at the Sugar APIs and shows how to develop and debug a graphical activity in Sugar using Python. Improve security with polyinstantiation If you're concerned about protecting world-writeable shared directories such as /tmp or /var/tmp from abuse, a Linux Pluggable Authentication Module (PAM) can help you. The pam_namespace module creates a separate namespace for users on your system when they login. This separation is enforced by the Linux operating system so that users are protected from several types of security attacks. This article for Linux system administrators lays out the steps to enable namespaces with PAM. Systems Administration Toolkit: Log file basics A typical UNIX or Linux machine creates many log files during the course of its operation. Some of these contain useful information; others can be used to help you with capacity and resource planning. This article looks at the fundamental information recorded within the different log files, their location, and how that information can be used to your benefit to work out what is going on within your system. Building your own memory manager for C/C++ projects Performance optimization of code is serious business. It's fairly common to see a piece of functionally correct software written in C or C++ that takes way too much memory, time, or, in the worst case, both. As a developer, one of the most powerful tools that C/C++ arms you with to improve processing time and prevent memory corruption is the control over how memory is allocated or deallocated in your code. This tutorial demystifies memory management concepts by telling you how to create your very own memory manager for specific situations. Role-based access control in SELinux Role-based access control (RBAC) is a general security model that simplifies administration by assigning roles to users and then assigning permissions to those roles. RBAC in Security-Enhanced Linux (SELinux) acts as a layer of abstraction between the user and the underlying type-enforcement (TE) model, which provides highly granular access control but is not geared for ease of management. Learn how the three pieces of an SELinux context (policy, kernel, and userspace) work together to enforce the RBAC and tie Linux users into the TE policy. SNMP-based monitoring for GPFS clusters New in version 3.2, IBM General Parallel File System (GPFS) on Linux provides Simple Network Management Protocol (SNMP) services that let administrators collect SNMP data about the health of a GPFS cluster so that problems such as disk failure can be quickly identified. The system lets a collector node gather the trap information, which an administrator can then monitor and analyze remotely on a separate management node. This article provides a method for basic verification of SNMP in a GPFS cluster. Explore Ubuntu Mobile and Embedded Ubuntu is a great server and desktop distribution for the GNU/Linux operating system, but did you know that it's also ideal for handheld and mobile embedded devices? Ubuntu's latest release, Gutsy Gibbon, now includes support for the embedded and mobile spaces with the Ubuntu Mobile and Embedded (UME) project. Get to know the UME project, and find out how to get started. Cell/B.E. container virtualization, Part 2: Implementation issues This three-part series illustrates a hardware-resource-focused form of software virtualization known as container virtualization (or operating system virtualization), demonstrated through the open source project OpenVZ. The series provides a comprehensive overview of all the components and techniques needed to virtualize the Cell/B.E. processor with software methods. This second article of the series details the implementation of dedicated virtualization and partitioning that was described in Part 1 of the series. Multiprocessing with the Completely Fair Scheduler The Linux 2.6.23 kernel comes with a modular scheduler core and a Completely Fair Scheduler (CFS), which is implemented as a scheduling module. In this article, get acquainted with the major features of the CFS, see how it works, and look ahead to some of the expected changes for the 2.6.24 release. Networking scalability on high-performance servers The proliferation of high-performance scalable servers has added a new level of complexity to networking and system performance. In this article, learn how to optimize your multi-node, high-performance Linux system as it uses system board gigabit Ethernet adapters from 1 to 4 nodes. Take a look at problematic networking scalability situations and get tips on how to avoid the pitfalls. Application development for the OLPC laptop The XO laptop (of the One-Laptop-Per-Child initiative) is an inexpensive laptop project intended to help educate children around the world. The XO laptop includes many innovations, such as a novel, inexpensive, and durable hardware design and the use of GNU/Linux as the underlying operating system. The XO also includes an application environment written in Python with a human interface called Sugar, accessible to everyone (including kids). Explore the Sugar APIs and learn how to develop and debug a graphical activity in Sugar using Python. Cell/B.E. container virtualization, Part 1: Concepts, architectures, and tools This three-part series illustrates a hardware-resource-focused form of software virtualization known as container virtualization (or operating system virtualization), demonstrated through the open source project OpenVZ. The series provides a comprehensive overview of all the components and techniques needed to virtualize the Cell/B.E. processor with software methods. This first article of the series discusses the basic concepts involved, illustrates the salient points of the OpenVZ and Cell/B.E. architectures and how they work together, and describes some of the OpenVZ tools. LPI exam 301 prep, Topic 302: Installation and development In this tutorial, Sean Walberg helps you prepare to take the Linux Professional Institute Senior Level Linux Professional (LPIC-3) exam. In this second in a series of six tutorials, Sean walks you through installing and configuring a Lightweight Directory Access Protocol (LDAP) server, and writing some Perl scripts to access the data. By the end of this tutorial, you'll know about LDAP server installation, configuration, and programming. Linux on board: Auto-uploading Nokia N800 photos These three installments of Linux on board show you how to get started building applications for the Nokia N800 by way of a working example: using the camera feature to create a Webcam. In this third and final installment, write an automatic photo-uploading routine for the photos you've taken. Linux on board: Accessing the Nokia N800 camera These three installments of Linux on board show you how to get started building applications by way of a working example: using the camera feature to create a Webcam. In this installment, walk through the start of building a camera application using gstreamer to access the Nokia N800 device's Webcam. (It's not as much work as you might think, especially since we borrow from an existing application.)