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You can view .chm file using gnochm or kchmviewer under Linux. However sometime you cannot install these programs. There is a third alternative - arCHMage. It is an extensible reader and decompiler for files in the CHM format. This is the format used by Microsoft HTML Help, and is also known as Compiled HTML. arCHMage is based on python-chm binding to chmlib from GnoCHM project.

Samba software, is a free, open source implementation of networking protocols to share files between UNIX/Linux and Windows computers. There are many ways to set permissions to your Samba shares and improve security. This article will cover some of the basic permissions and permission precedence with examples.

Whenever a Linux system CPU is occupied by a process, it is unavailable for processing other requests. Pending requests must wait till CPU is free. This becomes a bottleneck in the system. Following command will help you to identify CPU utilization, so that you can troubleshoot CPU related performance problems.

The stress test of hardware (hard drive benchmarks) is a simplistic test. There are a number of benchmarking applications software that can be used as hard disk (storage) stress testing. My favorite is Bonnie++ software. Bonnie++ is a benchmark suite that is aimed at performing a number of simple tests of hard drive and file system performance. Then you can decide which test is important and decide how to compare different systems after running it.

For security and to save bandwidth you may wish to configure Squid proxy server to block content. You do not want users to download files having extension such as MP3, MPEG, MPG, AVG, EXE etc This tutorial explains simple but effect squid content filtering using access control list to block files easily.

A Buffer overflows is a serious security problem. It allows an attacker to inject executable code of their choice into an already-running application. This ability to run arbitrary code at certain memory addresses is dangerous as attacker being able to execute the instructions from anywhere in memory.
This howto explains use of DieHard software to protect popular application such as Mozilla firefox. It protects applications from as-yet unfixed bugs and security vulnerabilities that exploit them. Think of DieHard as a new line of defense against hackers, together with anti-virus protection and firewalls.

Here's a nice howto on using mod_rewrite under Apache and Lighttpd for temporary site outages. This tip will help you to disable a site for maintenance using mod_rewrite without redirecting url. Both Lighttpd and Apache webserver allows you to send this message to client using server side rewriting using mod_rewrite and php. This is useful if you are running popular database driven community or e-commerce website. Error 503 informs search engine that site is temporary out of service. A good idea if your websites is heavily depends upon search engine for selling products and services.

A dictionary attack is a technique for defeating a cipher or authentication mechanism by trying to determine its decryption key or passphrase by searching a large number of possibilities. You can be configured to verify that passwords cannot be guessed easily using Linux PAM module called pam_cracklib.so. This article describes this configuration.

When you cannot monitor your server for service availability, it is better to take help of automated monitor and restart utility...

Intrusions can take place from both authorized and unauthorized users. My personal experience shows that unhappy user can damage the system, especially if they have a shell access. Some users are little smart and removes history file (such as ~/.bash_history) but you can monitor all user executed commands.

This question is asked again and again. Short answer — copyright/IP laws prevent shipping all the software and technologies/plug-ins with each Linux distro. Some distributions come with all these goodies but they are not free. So how do I get mp3s and other stuff working? The following shows you the work around in most distributions!

You can browse Samba or windows share from Nautilus GUI file manager or command prompt using smbclient.

But SSLBridge allows you to browse Samba/windows share over Internet using secure VPN connection.

Users can access and manipulate files over the internet using a browser, as if they were at their own Desktop system. With this software you can access your corporate resources using your existing Active Directory Account username and password.

Sometime it is necessary to run a command or script on the last day of a month. There is old good hack that will decide whether tomorrow is the first day of the next month. All these years I was using *dirty shell script hacks* to create my own date manipulation utilities for backups and other admin task. Thanks to this project no more dirty work. yest is highly recommended tool for all seasoned UNIX admin.

There is so much to read, so little time! If that is the problem, you can read these solutions. It will help you cut through the clutter of information overload. Linux / UNIX Frequently Asked Questions collection offers solution to many common or uncommon problems. Usually it covers sys admin related issues. The questions are asked by Linux newbie or picked up from UNIX chat rooms.

This tutorial shows you how to upgrade/downgrade your Linux Ethernet port speed using command line options. It also explain how to set the interface speed, duplex or auto negotiation on boot up for Fedora Core/ Cent OS/ Red Hat enterprise Linux and Debian/Ubentu Linux using a shell script.

Faster swithing is just a click away. switchdesk is the command to switch from KDE to GNOME or viceversa. This command provides a simple method of choosing between the various desktop environments available under Fedora Core, Cent OS and Red Hat Enterprise Linux. If X Windows is running, switchdesk will bring up a dialog box which allows the user to choose between the available desktops installed on the system.

It is true that wget is ultimate command line downloader. But when it comes to download acceleration wget fails to deliver the download speed. Linux and UNIX oses can use Axel and prozilla programs. These programs opens more than one HTTP/FTP connection per download and each connection transfer its own, separate, part of the file. It may sound weird, but it works very well in practice. For example, some FTP sites limit the speed of each connection; therefore opening more than one connection at a time multiplies the allowable bandwidth.

Spam is unsolicited emails with advertisements, which costs money. According to one survey spam costs up to $1000 per employee per year. Spam is send without the permission of the recipients. According to wikipedia, in June 2006 55 billion spam emails send per day. The book SpamAssassin is a practical guide to configure and install one of the most popular open source spam filter software.

Email is one the killer application of Internet. It is the easy method of composing, sending, storing, and receiving messages over electronic communication systems. However many new sysadmin finds it difficult to setup and maintain an email server system. This book is aimed at all new sysadmin who wish to learn the basis of mail server, setup & configuration issues, and advanced topics such as spam/virus protection. This book gives you just what you need to know to set up and maintain an email server.

Hardware and Software failures are part of Life. That is why you need to have a backup. However, you need not to backup all installed binaries (mostly software). In order to reinstall or restore your installed software you need to have a list of all installed software. This tutorial show how to backup list of installed software and apply it when needed after crash. It will not just save your time but both Debian and RHEL distro can update them instantly for you.