Linux Commands section is for learning the linux commands with examples.We will include basic to advance commands which is generally required for system administration task.
In this tutorial we will learn, how to extract RPM package on Linux system. Extracting the rpm has one the important command and it will surely help you in System Administration. Many times I solved some problem which is caused by file corruption of particular package. Here is the story from my experience.One day,my colleague…
In this tutorial we will learn,how to free pagecache, dentries and inodes from memory on linux systems. The linux system is quite capable to manage the memory itself.Sometimes we require to flush the cache from memory in linux system . On writing the file /proc/sys/vm/drop_caches cause the kernel to drop clean caches, dentries and inodes…
In this post we will learn, how to create new directory in Linux system.Directory also called as folder(In Windows System). To create a new directory in Linux system we will use the command called mkdir. By using some options with mkdir command, we can do many things. To create a directory in Linux Use the…
While configuring the rsyslog, without verifying we hit the semanage command. And result was with error – bash: semanage: command not found . The method is applicable to Red Hat based operating system like RHEL 6 and CentOS 6.
In this tutorial,we will learn how to use yum command to download rpm file without installing in linux system.It was before RHEL 5 arrival, when I used to download the source rpm packages by using up2date -d package-name Now things are changed,in Red Hat based Operating System above version 5.x . We use the yum…
Question : I am newbie in Linux.I have a question,How to read logs which are writing continuously.I am using the Linux CentOS Server and wants to read the mail.log which is filling continuously.I just want to read the logs at the same time,when log file writing is running Answer: To read the file which are…
In this post we will learn about how to save iptables permanently on Ubuntu.When we work on Red hat based Operating system like RHEL and CentOS.We can permanently set the iptables rule in /etc/sysconfig/iptables file . When you work on Ubuntu Operating System,you may find you are only able to set the iptables rule temporarily….
In this article we will learn how to temporarily change the shell after login in Linux. The user can change its shell without doing logoff and restart the machine.For example a user require to change the shell in system to perform various commands.
In this post,I am sharing a useful option with linux grep command.In this tutorial, we will use grep command to show lines after and before the keyword . As a Linux System Engineer, sometimes I get the requirement to print lines above and below of a particular keyword in the file. Generally if you only…
In this post I am sharing a small and useful tip about, how to know last command run successfully in Linux and Unix .The post will explain ,to get the exit status of command used last time. As a System Engineer, sometimes I have to check the success status of last command I run on…
Here in this post,we will learn very useful alias command with examples.In linux and Unix like operating system,mainly we use the alias command to shorten the long command.It is something like instead of writing long command in terminal,you type a few letters on terminal and your desired command get run. To understand the meaning of…
In this tutorial we will learn,how to install libjpegtran by using yum command in CentOS 6.x. The libjpegtran is mainly used for optimizing the jpeg and jpg format files.This utility compress an image without losing the quality of file. If you are running a website which has lots of jpeg/jpg file, which may take time…
Manual pages are software documentation found in Unix like Operating system and man linux distro. To get the information about package and command, we use the syntax yum install Package_name-Command_name.The abbreviation of Manual Page is man page . When you work in Unix like operating system,we generally need help and information about the package and…
In this tutorial we will learn about how to set user password by using encrypted password in command line.We assume you already know about how to simply set/reset password of user by using command (passwd username). In this tutorial,first we will encrypt the password in python interpreter then we use the output in one liner…
In this tutorial we will learn about linux command to find last modified and access date of a file/dir and filesystem.The command is very useful for troubleshooting purpose. Here we will use the stat command which display file or file system status. To find the last modified and access date of a file/dir/filesystem in linux,we…