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How to allow users to execute sudo command in ubuntu
If you have a user account that cannot make sudo command then it because it is not in sudoers list. You must add the user to sudoers list to allow sudo command. Sudoers list is located in /etc/sudoers
So open up the file with visudo command. You must use this command to edit this
No CommentsHow to add users and usergroup in ubuntu using terminal
It is very easy to create new user account in ubuntu using terminal. Just follow adduser and addgroup command.
Here is an example
I want to create a user named "nutch" with a new "nutch" user group. Here is how I did it.
No CommentsChange root user password in ubuntu using terminal (The short way)
If you forget the root user password you can change with a simple tricky command in ubuntu. Login to your regular account. You should have the sudo comman available for your user account.
Now open the terminal and enter the command
sudo passwd
This will let you to change root account password as you used sudo! Now enter the new password and confirm. Yes! You are done 
Execute shell command on server using php
Accessing shell command in server may not be available for you at all due to security reasons. But still you can access it using php since this will give you some extra features and time saving efforts. One of the example is to creating backup of your files. You might want to create backup of your files in gz format. But you may not have this feature in your cpanel or being banned by your hosting company. If you can make access to the shell of your server and execute tar command who can stop you from??!!
No CommentsCreate or extract tar files in ubuntu using terminal command
Ubuntu applications comes as tar packages, so if you want to create or extract tar files you should know the command of doing this
working with tar files in ubuntu
Create tar file
$ tar -cvf filename.tar filenameNo Comments