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 […]
linux command
Save iptables permanently on Ubuntu
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. […]
Temporarily change the shell after login
This is a useful trick to temporarily change the shell after login. The user can change its shell without doing logoff and restart the machine.For eg. a user require to change the shell in system to perform various commands. What is shell ? A Unix shell is a command-line interpreter or shell that provides a […]
grep command to show lines after and before the keyword
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 […]
How to know last command run successfully : Linux / Unix
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 […]
learn very useful alias command with examples
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 […]