Most applications normally display a feedback using asterisks (*******) when a user is typing a password, but on the Linux terminal, when a normal user runs the sudo command to gain super user privileges, he/she is asked for a password, but no visual feedback is seen by the user while typing the password.
Take a look at the following screenshot, here the user rootadminz has invoked the sudo command to install the vim text editor in CentOS 7, but there is no visual feedback as the password is typed (in this case the password has already been entered):
$ sudo yum install vim
You can enable the password feedback feature in /etc/sudoers file, but first create a backup of the file, then open it for editing using the visudo command.
$ sudo cp /etc/sudoers /etc/sudoers.bak $ sudo visudo
Search for the following line.
And append pwfeedback to it, so that it looks like this.
Now press Esc key and type :wq to save and close the file. But if you are using nano editor, save the file by hitting “Ctrl+x” and then “y” followed by “ENTER” to close it.
Then run the command below to reset your terminal for the above changes to start working.
That’s it, now you should be able to see a visual feedback (****) every time when you typing a password on the terminal, as shown in the following screenshot.
$ sudo yum update