Sunday, September 30, 2007

A Linux Toolbox for AMD64 Developers.

While you can't judge a book by its cover, you can often judge a development platform by its tools. By that measure, the AMD64 platform demonstrates a maturity that exceeds the youth of its release, in early 2003. The breadth of 64-bit tools available for the Opteron more.

Saturday, September 29, 2007

Metaclass programming in Python.

Too much cleverness in programming makes designs more complicated, code more fragile, learning curves steeper, and worst of all, it makes debugging harder. read full article.

Friday, September 28, 2007

Configuration/installation of ndiswrapper.

Lately i noticed alot of people asking questions about how to configure wireless for dell inspiron 1501 Laptops - this article will help you to get over it.
Dell TrueMobile wireless cards are based on Broadcom Wireless chipsets.
Dell recommends using the ndiswrapper driver framework for TrueMobile wireless cards. While not officially tested or supported by Dell.

Creating dynamic swap space.

When a GNU/Linux machine runs out of physical memory it will start to use any configured swap-space. This is usually a sign of trouble as swap files and partitions are significantly slower to access than physical memory, however having some swap is generally better than having none at all... read more.

Thursday, September 27, 2007

Sun Solaris for AMD64—What It Will Mean?

Sun's Solaris will soon appear in a native 64-bit version for the AMD64 architecture. While you can already run the 32-bit version of Solaris x86 today, Alan Zeichick explains the significance of this new operating system release, and highlights Sun's plans to support the AMD Opteron and Athlon 64 processors.

Ten more command-line concoctions.

A great number of shell features affect how the command name you type is interpreted. Each shell has an assortment of built-in commands; the PATH environment variable specifies the list and order of directories to search; and each alias acts as shorthand. With so many ways to run a program, how do you know what you're actually executing? Use the built-in type command of the shell to reveal the truth. read more.

Wednesday, September 26, 2007

Linux IPv6 HOWTO.

The goal of the Linux IPv6 HOWTO is to answer both basic and advanced questions about IPv6 on the Linux operating system. This HOWTO will provide the reader with enough information to install, configure, and use IPv6 applications on Linux machines.

Tuesday, September 25, 2007

Firewall and Proxy Server HOWTO.

This document is designed to describe the basics of firewall systems and give you some detail on setting up both a filtering and proxy firewall on a Linux based system.

Monday, September 24, 2007

Managing your IP space with Perl.

This tutorial discusses many common tasks along with solutions using NetAddr::IP. Since Perl lacks a native type to represent either an IP address or an IP subnet.

Automated Backups With rdiff-backup.

This tutorial describes how to do automated server backups with the tool rdiff-backup. rdiff-backup lets you make backups over a network using SSH so that the data transfer is encrypted. The use of SSH makes rdiff-backup very secure because noone can read the data that is being transferred. rdiff-backup makes incremental backups, thus saving bandwidth.

Sunday, September 23, 2007

Application configuration with Perl.

File-based configurations break down quickly if you use a hand-built method. Teodor Zlatanov demonstrates how the AppConfig module can handle local configuration storage for Perl programs, and how such configurations can be stored in a database that can then be accessed from any machine on the network.more.

Saturday, September 22, 2007

Controlling the duration of scheduled jobs.

Terminating a job after a certain time, or after other criteria are met, usually involves having one process to run the job and another to monitor the completion criteria. In this tip you learn how to have a process manage the time while the real job runs. You also learn how to use the signal and trap facilities to terminate one of these tasks if the other finishes prematurely.

Thursday, September 20, 2007

Windows to UNIX porting,

Software programs are often made to run on systems that are completely different from the system in which the program is coded or developed. This process of adapting software across systems is known as porting. You might need to port software for any one of several reasons read more...

FreeBSD - Debugging a Kernel Crash Dump with kgdb.

Once a dump has been obtained, getting useful information out of the dump is relatively easy for simple problems. Before launching into the internals of kgdb(1) to debug the crash dump, locate the debug version of your kernel (normally called kernel.debug) and the path to the source files used to build your kernel.. more

Wednesday, September 19, 2007

Gentoo Initscripts.

Gentoo uses a special initscript format which, amongst other features, allows dependency-driven decisions and virtual initscripts. This chapter explains all these aspects and explains how to deal with these scripts.

Using kvm, or kqemu, to speed up qemu.

Have you ever wanted to play with a new distro without having to burn and then reboot into a liveCD or do an install into a spare partition that you may or may not have? QEMU has been an option for awhile but it is slow. There are several options available to run up a virtual machine. read more.

Sunday, September 16, 2007

Running 32-bit Applications on 64-bit Debian GNU/Linux.

Advanced Micro Devices (AMD) developed a series of 64-bit extensions to their 32-bit RISC-based Intel IA-32 (i386) compatible processors. AMD sell their AMD64 (x86-64) architecture processors under a range of names: Athlon 64; Turion 64; Phenom; Opteron and Sempron (only the latest generation).read more.

The Ultimate Do-It-Yourself Linux Box.

Some of us just like to do it ourselves. There's something uniquely satisfying about selecting every component in a system. It allows you to balance the exact price/performance trade-off that suits you best. Do-it-yourself is also one of the best ways to ensure that you have a system that won't become obsolete within six months. For example, most AMD64 motherboards support only 4GB of RAM, but our favorite board supports up to 8GB of RAM. We may never upgrade it to the full 8GB, but it's nice to have that room for expansion. You may not get that kind of room for expansion with a pre-made system.

Saturday, September 15, 2007

Tuning Apache and PHP for Speed on Unix.

how to optimise Apache on Linux for PHP and CGI programs. These tips can also apply to Perl and Python

Friday, September 14, 2007

Installing clamav-milter for FreeBSD.

The open-source ClamAV (Clam Anti-Virus) virus scanner can be invoked in a variety of ways. This document describes my experience in installing it as a sendmail milter from the FreeBSD ports.

Thursday, September 13, 2007

File management in Linux.

Unix systems provide a number of commands to manage files and directories. Their strong point is the ability to use them in a rather simple manner against a group of files/directories meeting certain conditions. For example all the files satisfying specific criteria can be deleted or have their names changed en masse.more...

Wednesday, September 12, 2007

Systems Administration Toolkit: Testing system validity.

The typical UNIX® administrator has a key range of utilities, tricks, and systems he or she uses regularly to aid in the process of administration. There are key utilities, command-line chains, and scripts that are used to simplify different processes. read more.

Tuesday, September 11, 2007

Building a Linux firewall.

The growth of the Internet has prompted many organizations to become security-conscious. Documented and undocumented incidents of security violations, expanded research about security issues, and even media hype have brought about the potential for at least partial solutions for securing a networked environment---without completely isolating the network from the outside world. Leading the pack of solutions is the firewall. Just about everyone has defined what a firewall is, so I won't be any different.more.

Monday, September 10, 2007

Python for system administrators.

Adopt Python to manage UNIX® systems while incorporating concepts of good program design. Python is an easy-to-learn, open source scripting language that lets system administrators do their job more quickly. It can also make tasks more fun. read more.

Sunday, September 09, 2007

The C programming language - Learn GNU C with C Book.

This is the online version of The C Book, second edition by Mike Banahan, Declan Brady and Mark Doran, originally published by Addison Wesley in 1991. This version is made freely available. Download it from here.

Synchronize your PalmOS® Handheld over Bluetooth in Linux.

This HOWTO will describe how to connect your Palm handheld over Bluetooth to your desktop/laptop or server machine. Once connected, you can then synchronize your Palm, or surf the web, or play mp3s or many other things.

Saturday, September 08, 2007

BSD Sockets: A Quick And Dirty Primer.

As you delve into the mysteries of UNIX, you find more and more things that are difficult to understand immediately. One of these things, at least for most people, is the BSD socket concept. This is a short tutorial that explains what they are, how they work, and gives sample code showing how to use them.

Friday, September 07, 2007

Set up a Web server cluster in 5 easy steps.

To get the most out of this article, you should be familiar with Linux and basic networking, and you should have Apache servers already configured. Our examples are based on standard SUSE Linux Enterprise Server 10 (SLES10) installations, but savvy users of other distributions should be able to adapt the methods shown here.

Thursday, September 06, 2007

FreeBSD Security Advisories.

Like many production quality operating systems, FreeBSD publishes “Security Advisories”. These advisories are usually mailed to the security lists and noted in the Errata only after the appropriate releases have been patched. This section will work to explain what an advisory is, how to understand it, and what measures to take in order to patch a system.

Wednesday, September 05, 2007

Securing 802.11 with OpenBSD.

How can we make sure that our WLAN traffic is useless for all unauthorized listeners? From the OSI layer 3 point of view, 802.11 is not different than any other LAN technique (ethernet, token ring..). This makes it possible to use standard solutions for securing IP traffic.
This document describes an implementation of 802.11 wireless LAN access point and VPN gateway using the OpenBSD operating system and how to secure the WLAN traffic with IPsec. We are going to utilize many of the hot Internet buzzwords

Multicast over TCP/IP HOWTO.

This HOWTO written by Juan-Mariano de Goyeneche tries to cover most aspects related to multicast over TCP/IP networks. So, a lot of information within it is not Linux-specific (just in case you don't use GNU/Linux... yet). Multicast is currently an active area of research and, at the time of writing, many of the "standards" are merely drafts. Keep it in mind while reading the lines that follow.

Tuesday, September 04, 2007

Solaris 2.6 Firewall, Example Installation & Configuration

This procedure details one way, of many, to configure a secure firewall platform based on Sun Solaris. It will be too restrictive for most other uses.It may even be too restrictive for your firewall. No warranty is made regarding the accuracy or reliability of this document. Use it at your own risk.

Monday, September 03, 2007

Configuring a Cron Task.

The crontab command, found in Unix and Unix-like operating systems, is used to schedule commands to be executed periodically. It reads a series of commands from standard input and collects them into a file known also known as a "crontab" which is later read and whose instructions are carried out. read more.

Saturday, September 01, 2007

Configuring the Cisco VPN 5000 Client to the Cisco VPN 5000 Concentrator with Cisco Secure UNIX (RADIUS) Authentication.

The Cisco VPN 5000 Concentrator can be configured to authenticate VPN 5000 Clients through Cisco Secure UNIX (CSUNIX) RADIUS. This document assumes that local authentication works prior to adding RADIUS authentication (hence our user localuser in group ciscolocal). Authentication is then added to Cisco Secure UNIX RADIUS for users that do not exist in the local database (user csunixuser is assigned to group csunix by virtue of the attributes returned from the Cisco Secure UNIX RADIUS server).

Simplified kernel extensions with AIX Version 6.

Discover why you need to change your applications and build environments that supply 32-bit-only kernel extensions to accommodate IBM AIX® Version 6. With AIX Version 6, the kernel environment is 64-bit kernel only. Previously, the AIX operating system provided both 32-bit and 64-bit kernels, requiring 32-bit and 64-bit kernel extensions. In this article, apply two easy solutions to help you make the transition and start reaping the benefits of the simplified kernel environment.