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How To Preserve Symbolic Links In Tar Command

How to preserve symbolic links especially when you tar the files is explained below. We all know how to use tar command. Below option shows the way to preserve links when you archive. Example: # tar -cvhf archive.tar /backupfolder Note: What you need to remember is that when tar archives a symbolic link, it writes a […]

May 27, 2011 | By
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7 Examples On Linux Rar Command For Compression

RAR is a file format used for data compression and archiving. The command was developed by Eugene Roshal and is used to create compressed files. The RAR format supports data compression, error recovery and file spanning. It supports files larger than 4 gigabytes. RAR files can only be created through commercial software. You can unpack […]

May 24, 2011 | By
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Linux - Manage Spaces And Special Characters In File Name

In Linux, whitespace is a special character and one of the most frequently used characters. It separates the commands or arguments to the commands. For example, the copy command treats the first file assigned to it as the source file and the second file as the destination file. These two file arguments are separated by […]

May 24, 2011 | By
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Explained Linux Kernel Tuning Using Sysctl (/etc/sysctl.conf)

Sysctl is a powerful Linux command which acts as an interface to dynamically change the kernel parameters. With the help of this command, you can modify the kernel parameters without recompiling the kernel or rebooting the machine. The parameters available for modification can be found under /proc/sys directory. So, procfs (file system simulation to be […]

May 24, 2011 | By
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7 Examples To Delete/Erase Contents Of File In Linux But Not File

Deleting a file in Unix/Linux is as simple as issuing the “rm” command (with file name as an argument). But here, we present some methods that will empty your file rather than deleting it. It means that the contents of the file will be removed and not the file itself. In the following methods, we […]

May 23, 2011 | By
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How To Add And Configure Remi Repositories In Linux

The official packages shipped with enterprise Linux such as RHEL contain packages that are officially supported by Red Hat Inc. These are stable packages but these are not up to date. But sometimes you might require some latest packages for your web-based services and applications such as latest versions of MySQL and PHP. You can get these […]

May 21, 2011 | By
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Linux SSH Configuration And How To Disable SSH Direct Root Login

SSH is the secure shell for remote login. SSH provides an encrypted and secure communication for accessing a remote machine. You can login to a machine on the network and execute commands on it as if it was present locally. SSH has replaced telnet and other insecure remote shell protocols. In telnet, all the data along with […]

May 21, 2011 | By
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Semaphore error (semget)-Apache crash

The issue causes mainly due to insufficient disk space available for apache resources. Fixes: 1. Check /etc/httpd/domlogs, if it is motre than 2GB that will cuase the issue; reduce the size and restart apache. 2. Check the error_log, access_log and other log files if anything is above 2B that will cause the issue; reduce the […]

May 21, 2011 | By
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What Is Safe Mode In PHP: Need For Disabling/Enabling PHP Safe Mode

What is safe mode in PHP? The PHP safe mode is an attempt to solve the shared-server security problem. When safe mode is on, PHP checks to see if the owner of the current script matches the owner of the file to be operated on by a file function or its directory. For example: -rw-rw-r-- […]

May 18, 2011 | By
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Example How To Add Directories To PATH Variable In Linux

The environment variables control the behavior of the shell. Environment variables are the variables that set the working environment of the shell. Some of the environment variables are USER, HOME, SHELL, PWD, SHELL, PS1, PS2, etc. The HOME variable contains the path of home directory of the user. Similarly, the other variables contain other values […]

May 18, 2011 | By
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20 Examples for Linux Zip and UnZip Command

As an administrator, you often are called upon to deal with file archives, which are one or more files that have been packaged into one file and sometimes compressed. Linux system has some methods for compression and decompression processes. It helps when you have some files and need less space used in your system, to create […]

May 18, 2011 | By
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Set Date And Time In Linux And Sync With Hardware (CMOS)

Why are the date and time important? Having the correct date and time in your Linux box is very important. When you use emails ,the default time used by the application is the system calendar's date and time. Unless otherwise you have specified a different time scale. If you work in a client server network, most of […]

May 18, 2011 | By
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Need For Filesystem Check / Repair ( fsck ) On Linux

Why fsck? Any Linux user must have experienced file corruptions and booting failures at least once in their life. Being an I.T professional for many years, I have encountered this problem many times. Linux comes with a handy command called 'fsck' to save you. Fsck stands for File System Consistency Checker. When and Where to use fsck? […]

May 18, 2011 | By
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What Is SYN Flood Attack? Detection & Prevention In Linux

What is SYN Flood Attack? A SYN flood attack is a form of denial-of-service attack in which an attacker sends a large number of SYN requests to a target system’s services that use TCP protocol. This consumes the server resources to make the system unresponsive to even legitimate traffic. This attack can occur on any services that […]

May 18, 2011 | By
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