Most useful Linux commands for DevOps

 

To use and get comfortable with Linux, you need to learn Linux commands. Most of things in Linux is done by terminal. So you need to know some commands of Linux to work Linux terminal. Here in this blog I have find some commands that is very useful in DevOps area as per my perspective. 

So here, In this blog I have figured out some Linux commands. This commands are very useful when you interact with Linux terminal to get your work done. In DevOps job, We need to deal with configuration, solving errors, maintenance etc.. .Therefor we have to know this useful Linux commands to automate process and get our work easier.

➤     Widely use Linux commands

• To find the description of each Linux commands in terminal

             man command-name

• To add-user / add-group in system

            sudo adduser user-name

• To change ownership of file

            chgrp user-group filename

• To change file access permission

            chmod a+rwx filename

        (where a = user for give permission to all class

                     r = read, w = write, x = execute )      

• To give alias name to Linux command but it works till the terminal open. It destroy when you restart terminal.

            Syntax : - alias alias-name='Linux command'

            Example : - alias download='cd ~/Downloads'

• To give permanent alias name to Linux commands open .bashrc file in edit mode in terminal ( $nano ~/.bashrc ) , At the end write your alias name

              Syntax : - alias alias-name='Linux command'           

              Example : - alias download='cd ~/Downloads'

• To update new software package

              sudo apt-get update

• To content of file in terminal window

              cat filename

• To run command periodically with frequency defined in days, weekly, and months. Add following command at the end of ( /etc/anacrontab ) file.
  

              Syntax : - period delay job-name command

              Example : -  @daily 10 example.daily /home/nikunj/script/backupsync.sh

• To display 10 last line of file

              tail -n 10 filename.txt

• To copy file in terminal

              Syntax : - cp option source destination

              Example : - cp /home/file ~/

             (to move directory  use -R option )

• To display disk space of system

              df -h

              df -hT /home

• To find file in directories

             find . -type f filename.txt ( . indicate current directory)

             find . -maxdepth -newermt "2020-01-30" (find file on by date of modifies) 

• To search for  specified pattern in file

             grep 'hello' file.txt

• To display cpu and memory usage

             top

• To display system info

             uname -a

• To search repository

             apt-cache search file-name*

• To check currently logged in user

             w

• To check network activity and configuration

            netstat

            sudo netstat -ln  | grep -w "3000" ( To find particular port which in use or not )