Linux commands for a DevOps

These are various linux commands that a DevOps should know:-

ls

This command is used to list down the contents in a particular directory.Its syntax is

ls <paramaeter>

mkdir

This command is used to make a directory/folder in your system.Its syntax is

mkdir <directory-name>

mv

This command is used to move a file from one place to another. Its syntax is

mv /path/to/filename <destination>

cp

This command is used to copy a file from one place to another. Its syntax is

cp /path/to/filename <destination>

cp -r

This command is used to recursively copy a file or directory from one place to another.

cp -r <file/directory-name> <destination>

cd

This command is used to change to a particular directory. Its syntax is

cd <directory-name>

cat

This commands is used to concatenates a given file.Its syntax is

cat <filename>

rm -r

This command is used to recursively remove a file or directory.

rm -r <file/directory-name>

touch

This command is used to create a particular file. Its syntax is

touch <file name>

echo

This file is used to write content to a particular file. Its syntax is

echo <your-text> > abc.txt

is aredirectional operator

vim

It is an editor that don’t comes on default. You need to install it on your system be executing

sudo apt install vim –y

For editing a file using vim execute below command

vim <file-name>

For exiting from vim press : and then write wq which means write quit

nano

This is an editor that comes by default, If it’s to see s not installed somehow then execute below command to install it

sudo apt install nano -y

For editing a file in nano execute

nano <file-name>

For exiting from nano press ctrl+x then press y for yes

sudo

This command is used to provide the root privileges, where sudo means SUPER USER DO. Its syntax is

sudo <command>

sudo useradd <username>

sudo passwd <username>

sudo userdel <username>

sudo groupadd <groupname>

sudo groupdel <groupname>

sudo usermod -g <groupname> <username>

chown

This command is used to change the owner or group of a particular file. Its syntax is

chown <owner-name> <filename>

history

This command is used to check the history of all the commands executed on the server. Its syntax is

history

date

This command is used to show the date on the server, to see the date on server simply execute

ssh-keygen

This command is used to generate the public/private key on the server. Its syntax is

ssh-keygen

df -h

This command is used to check the disk space on a server. Its syntax is

 df –h

apt-get

This command is used to handle packages in linux. Its syntax is

sudo apt-get <options>

htop

This command is used to check the load average on the server. Its syntax is

htop

ifconfig

This command is used to view/configure network interfaces. Its syntax is

ifconfig <options> <interface>

wget

This command is used to download any package from internet to system. Its syntax is

wget <url-of-package>

tail

This command is used to display last part of a file. Its syntax is

tail -f <file/location>

-f stands for follow

grep

This command is used to search the file patterns. Its syntax is

grep <pattern-name>

list users

For listing the users in the server execute the below command

awk -F':' '{ print $1}' /etc/passwd

scp

SCP stands for secure copy, for copying a file from local to server execute below command

scp -i <path-to-pem-file> <path-for-file-to-be-copied> user@<server-ip>:<path/on/server/where/file/to/be/copied>

Copy a file from server to local system environment

scp -i /path/to/pem-file user@your-ip: path/to/file /your/local/directory/files/to/download