Chroot Linux

Chroot creates jail environment on Linux systems blocking access to files out side of chroot directory. As a security measure you can chroot lot of applications like Bind, FTP, SSH, etc. Chrooting can be also used where you dont want to give access to sensitive system resources.Following are the steps to create a chroot environment for SSH login. We will first build a chroot tree, we will copy minimal binaries required for remote login. After this its up to you what other tools you want to make available for users.

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Typing Special Characters in GIMP

Ever tried to add Copyright © or Registered ® symbols as a Text in image using GIMP. These symbols are not directly available on your keyboard nor GIMP has onscreen keyboard to type such special characters. But GIMP indeed supports these, here it is how.
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Postfix Header Checks

Quick way to filter your mails using postfix header checks.

Postfix has built in content inspection using header and body checks. You can use this feature to block unwanted spam, virus emails.
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Adding New Partition to Xen VM

Xen VM partition are usually created under LVM. This provides facility to expand/shrink them on demand. Following are the steps to add new partition to your VM.

 

Hardening Linux System

A non harden server is an open invitation for hackers and intruders. Although linux installation will by default configure your firewall and selinux to allow access to necessary service like SSH but this is not sufficient. Lot of services which start by default are not required for most of the setups. Partition like /tmp and /var/tmp are required to be secured. These partition allow to store files for all users and have sticky bit set to stop file modifications by other users.

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Custom Linux Distribution Using CentOS5

How many times you have started installation from scratch for your new server. Each time you follow those same steps to build a server. Anaconda installer will make things easy for you, by providing KS file for unattained installation. But what about your custom packages and script those are not present in your distribution? You manually download and configure them. Anaconda can also take care of your own RPMs, scripts and custom installation. Following guide will help you to make your own installation DVD/CD using existing Centos 5 DVD (more…)

Auto USB Backup Your Linux Box

Linux udev device manager dynamically provides nodes for the devices actually present on a system. Linux distributions with Kernel 2.6.x are included with this support unless it is manually disabled. Traditionally /dev partition use to contain static files to access devices.