Normally, the login screen in Ubuntu shows a user list from which you can select one, enter the password and login to the system. Many times, due to security reasons, you may not want to have a list of users displayed on booting into the computer. There is a method to hide the users list on the login screen. You need to edit the lightdm.conf file in the path /etc/lightdm. You will then need to enter a User ID and the password to login to the system. To do so, open up the terminal window and do the following steps:
Start up the terminal on your system, then enter the commands in italics as shown below.
The below creates a backup file of the lightdm.conf file.
$ sudo cp /etc/lightdm/lightdm.conf /etc/lightdm/lightdm.conf.orig <enter>
If you are comfortable using the vi line editor in linux, the below opens the lightdm.conf file for editing.
$ sudo vi /etc/lightdm/lightdm.conf <enter>
Add a line as shown in italics below after “user-session=ubuntu” and save the lightdm.conf file.
If you do not want to use vi, you can use gedit as follows:
$ sudo gedit /etc/lightdm/lightdm.conf <enter>
Add the line:
and save the file.
When done, the lightdm.conf file should have the following lines shown in blue which you can view giving the cat command as follows:
$ cat /etc/lightdm/lightdm.conf <enter>
Restart and you should find that you are now asked to enter your User ID instead of selecting it from a list.