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Installation & Configuration of "High Availability Cluster (Heartbeat)" on RHEL 6 Node names are, station1 & station2 Give below command to set the host name on both Linux machines. “hostname station1” IP Address of “station1” is 192.168.1.1 “hostname station2” IP Address is “station2” is 192.168.1.2 Edit “/etc/sysconfig/network” file & change the HOSTNAME to “station1 & station2” Note: - “uname -a” command should return “station1” & “station2” names respectively after rebooting both machines. - No need to mention VIP (Virtual IP) anywhere in Linux Network & Host configuration. Heartbeat will manage the VIP during “fail over” process in between “station1 & station2” Now, We are going to install “hearbeat”. Step:1 yum install heartbeat Total download size: 420 k Installing: heartbeat i686 Installing for dependencies: heartbeat-libs i686 3.0.4-1.el6 3.0.4-1.el6 epel epel Show dependencies Installing : heartbeat-3.0.4-1.el6.i686 Installing : heartbea...

Linux File Systems: Ext2 vs Ext3 vs Ext4 ext2, ext3 and ext4 are all filesystems created for Linux. This article explains the following: High level difference between these filesystems. How to create these filesystems. How to convert from one filesystem type to another. Ext2 Ext2 stands for second extended file system. It was introduced in 1993. Developed by Rémy Card. This was developed to overcome the limitation of the original ext file system. Ext2 does not have journaling feature. On flash drives, usb drives, ext2 is recommended, as it doesn’t need to do the over head of journaling. Maximum individual file size can be from 16 GB to 2 TB Overall ext2 file system size can be from 2 TB to 32 TB Ext3 Ext3 stands for third extended file system. It was introduced in 2001. Developed by Stephen Tweedie. Starting from Linux Kernel 2.4.15 ext3 was available. The main benefit of ext3 is that it allows journaling. Journaling has a dedicated area in the file...

The built-in disk defragmenter in Windows can’t selectively defragment individual files or folders. To do that, a cool utility named Contig is available for free from Microsoft Sysinternals team. It can defragment specified files and folders, a bunch of file types and thereby optimize disk space. Download it from here . Using it is simple, specify the path which contains specific files that need to be defragmented. For example, to defragment all the files in the folder named “music”, type : contig -s d:\music\ * . * The -s parameter instructs contig to perform recursive processing of all the subdirectories present in the given path. Once the defragmentation process is over, a summary is displayed regarding the same. To defragment files of only a specific extension say .avi in a folder named videos, type : contig -s d:\videos\ * .avi The above will only look for files with .avi extension and defragment them. Nice and effective. A very useful tool ...

Start The Runlevel 5 for RHEL 6/CentOS 6 Server. Few people might have faced an issue of starting GUI on runlevel 5 on RHEL 6/CentOS 6. When They Forgot Install or Select Desktop Installation. In case After The installation we can start the GUI on Our RHEL Machine by Following These simple steps.. 1). Install Desktop & Xorg Packages on system using following comamnd. # yum groupinstall "Desktop" "Desktop Platform" "X Window System" 2). Add followig line in /etc/inittab file to start the X11/GUI for switching to runlevel 5. exec /etc/X11/prefdm -nodaemon Done!