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This is a simple backup solution for people who run their own web server and MySQL server on a dedicated box or VPS. Most dedicated hosting provider provides the backup service using NAS or FTP servers. These service providers will hook you to their redundant centralized storage array over private VLAN.

The main advantage of using FTP or NAS backup is a protection from data loss. You can also generate a shell script as per your setup.

This article shows how to change a system password using a web based PHP script. This is one the essential tasks that many new sys admin find it little difficult as they are not familiar with PHP. Using concept presented in this article one can write extended edition with any other programming language such as Perl or Python.

The idea is very simple you want to limit who can use sshd based on a list of users. The text file contains a list of users that may not log in (or allowed to log in) using the SSH server. This is use for improving security.

Another option is to limit users using sshd's AllowUser or DenyUser directives.

This article shows how to recover from damaged ReiserFS filesystem. Linux comes with different filesystems and different repair utilities. With the help of GNU 'ddrescue' program one can copy data from one file or block device to another, it is a tool to help you to save data from crashed partition. reiserfsck program provides special options for repairing and recovering partition.

Reiserfsck searches for a Reiserfs filesystem on a device, replays any necessary transactions, and either checks or repairs the file system. ReiserFS saves data or log in a special file for pending disk updates and later on it commit updates to disk resulting into very good filesystem consistency.

In order to write DVD/DVD-RW from shell prompt you need to install a package called dvd+rw-tools.

DVD is another good option for backup, archiving, data exchange etc. You can install dvd+rw-tools with following commands. Also note that this package works under *BSD, HP-UX, Solaris and other UNIX like operating systems.

The book DNS in Action is a guide to DNS implementation, os specific configuration, and administration. This is a practical book for new sys admin and network architects about how to run and configure DNS. Libor Dostalek and Alana Kabelova has done a good work to put together complicated topic such as DNS and its implementation. The entire book is divided into ten chapters.

Chapter 1: Domain Name System
We humans take advantage of DNS whenever possible by using terms URLs and e-mail addresses. The first chapter explains the basis of DNS and its principles.

This is not a scientific comparison per se but more of an attempt to formulate the framework for comparison that might be used by future authors. Actually the fact that a particular person is interested in the theme to the extent that he/she wrote such a paper is a strong argument against his/her depth of knowledge in one or both OSes that he/she tries to compare ;-).

Author conclusion is as follows:

"All-in-all Solaris is a powerful, stable, conformant-to-standards OS that can run many open source applications as well as Linux, and some (mainly multithreaded applications) better than Linux. Like in the cases of Red Hat and Suse, the cost of support is extra, but it is more reasonably priced. Security patches are free which makes Solaris similar to Windows."

First, benchmarking a web server is not an easy thing. To benchmark a web server the time it will take to give a page is not important: you don’t care if a user can have his page in 0.1 ms or in 0.05 ms as nobody can have such delays on the Internet.

What is important is the average time it will take when you have a maximum number of users on your site simultaneously. Another important thing is how much more time it will take when there are 2 times more users: a server that take 2 times more for 2 times more users is better than another that take 4 times more for the same amount of users.

Here are few tips to carry out procedure along with an example.

LVM is an implementation of a logical volume manager for the Linux kernel. The biggest advantage is that LVM provides the ability to make a snapshot of any logical volume. A backup in which some of the files in the backup contain changes that were made after the files were checkpointed. This type of backup needs recovery before it can be made consistent. Inconsistent backups are usually created by taking online database backups; that is, the database is open while the files are being backed up. This article covers both old (read-only) partition and LVM snapshot methods to make a consistent backup.

Whichever BSD you use, the basics of package management are similar. Each member of the BSD family has a slightly different approach in this area, but all share common themes, as David Chisnall discusses in this article.

Main benefit of setting transparent proxy is you do not have to setup up individual browsers to work with proxies. This nice and simple guide explains how to setup a transparent proxy with Squid and iptables (DNAT) firewall in three easy steps.

You can speed up downloads or web page access time with Apache mod_deflate module. The mod_deflate module provides the DEFLATE output filter that allows output from your server to be compressed before being sent to the client over the network. This decreases the amount of time and data transmitted over the network, resulting in faster web experience or downloads for visitors.

Sarbanes-Oxley has forced many companies to start taking UNIX security seriously. Not a big deal. We all know how to secure a UNIX server: disable unnecessary network daemons; remove unnecessary software packages like compilers and debuggers; institute strict password and account parameters; and search and destroy world-writable files. The only thing that eludes us is how to secure and audit shell access. This is where Enterprise Audit Shell (EAS) comes in.

Eclipse is an open source community that provides a development platform and a collection of application frameworks for building software. Learn how to install and use Eclipse specifically for Linux running on IBM POWER processor-based systems. Learn, also, how to use Eclipse to compile and run applications through sample Java and C programs.

Network attached storage (NAS) allows using TCP/IP network to backup files. This enables multiple servers in an IDC to share the same storage for backup at once, which minimizes overhead by centrally managing hard disks.
The protocol used with NAS is a file-based protocol such as NFS or Microsoft's Common Internet File System (CIFS). Both of them allow storing backups using UNIX and Linux systems.
NAS are not just common in IDC or offices anymore, you can use for file sharing and backup at home. You can purchase 200+GB NAS for less than $200. However many new Linux or UNIX sys admin or home users find it difficult to use NAS for backup and sharing purpose. This tutorial covers how to access NAS from Linux using various methods.

This mini how-to shows you how to dual boot between AIX and Linux operating systems in a clustering environment, where available hardware resources are limited. The information presented in this document is based on actual experience. It should be used only by those who have some knowledge of system administration and skills in working with the IBM System p5 (formerly pSeries) architecture.

Linux and other UNIX like operating systems offer strong file permissions and POSIX ACL (access control list) concept in computer security used to enforce privilege separation.
However, none of them offers a password to protect files. This article explains howto use GNU gpg (GNU Privacy Guard) encryption and signing tool or mcrypt command to encrypt or decrypt files with a password with open source cryptographic software.

Programming a UNIX system can be fun as well as educational. With the UNIX strace tool and GDB, the GNU Project Debugger, you can really dig deep into the functionality of your system and learn a lot about the various programs that comprise it. Using both tools in concert can be a rewarding experience as you look under the hood of your UNIX machine.

Linux offers a number of file systems. This paper discusses these file systems, why there are so many, and which ones are the best to use for which workloads and data. Not all data is the same. Not all workloads are the same. Not all filesystems are the same. Matching the file system to the data and workload allows customers to build efficient scalable and cost effective solutions.

less is a pager or a program similar to more, but which allows backward movement in the file as well as forward movement. Less has a massive number of options.