Monday, 2 April 2012

How To Disable Password Prompts For sudo In Ubuntu

If you are one of those linux users who very frequently use the sudo command, you might have been annoyed of entering passwords each time you use this command. However with a very simple tweak, you can change this behaviour and disable the password prompts for the sudo command.


A bit of warning though, do not modify the default behavior of asking for passwords since it would drastically compromise security of your system. Following is the warning given by ubuntu help.

If you disable the sudo password for your account, you will seriously compromise the security of your computer. Anyone sitting at your unattended, logged in account will have complete Root access, and remote exploits become much easier for malicious crackers.

Now you are aware of warning, lets see how this can be done.We need to edit the /etc/sudoers file. Lets first open the file in safe editable mode using the following command:

samar@Techgaun:~$ sudo visudo

Using visudo for editing the /etc/sudoers lets us locate the possible errors that may occur while editing the file so always use visudo.

Following is the format of disabling password prompts for specific user.

<username> ALL=NOPASSWD: ALL

So if we are to disable password prompts for the user samar, you can make a new line with following entry:

samar ALL=(ALL)NOPASSWD: ALL

In case you want to let all the users with admin privilege use the sudo command without having to give the password, you can edit the line that says %admin ALL=(ALL) ALL to the following:

%admin ALL=(ALL)NOPASSWD: ALL

Once you add such line for appropriate user, press Ctrl + x and save the changes. You will either have to log out and login back or restart the shell to see the modification in effect.

I hope this is useful. :)