Linux basic commands

check the ip address

Check the hidden ip address which are not correctly configured

Change name servers of network

check gateway address

Find all files with in the system

Find all file and folder count

Find the total number of files/folder in a folder

Server shutdown

change password of current user

Change user

Change directory

ctrl + c to quit command

This command shows listing. l for long format, h for human readable, A for hidden files.

get list and permissions of the directories

Get directory listing & size

Get hard disk space information

Shutdown is the command and -r is a flag which is used by the shutdown command. In this case the -r means reboot. 0 is the time in minutes before the shutdown occurs.

How to change keyboard language layout?
sudo nano /etc/default/keyboard

Change the “gb” to the two letter code for your country.

Reboot the system to take effect

start the desktop

Install chromium browser

Make the browser more visually appealing enter the following

List all the usb connecting devices.

Use the Ctrl-Alt-F1 shortcut keys to switch to the first console.
To switch back to Desktop mode, use the Ctrl-Alt-F7 shortcut keys.

How to correct wrong server time

Get the current time

Correct & sync the server time

In this example, filename.tar represents the file you are creating and files/directories represents the files or directories you want to put in the new file.

Compressed tar files are conventionally given the extension .tgz and are compressed with gzip.

Copy all files in a tar file and also gzip it

unzip a compressed file

unzip an unrar file.

unrar x <filename>

copy file from server to server

Convert tar.gz to tar file

Unzip a gz file

copy and remove files from destination

change the ownership of a file or a directory

View cronjob file

edit cronjob file

Edit user cron jobs

Restart crontab service

find process id

-9 is special Kill signal, which will kill the process.

delete all mails from a username

list all fonts on ubuntu

install font on ubuntu

print history in a file

show file content

Check user group

nmap port scanner

Show possible locations of php

Change file permissions

Change file owner/group


mark a file executable

mount shared folder 

Sync folder or file to another server

upload files via ftp

Show apache compiled modules

Install php extension to see php error trance

How do I change the language via a terminal?

Check Ubuntu current version/release/codename

change password for webmin, if password lost

uninstall webmin

Check last login of user on server