Command to delete user password under Linux

Type the following command to delete a user password:

# passwd --delete username

OR

# passwd -d username

Above command delete a user's password (make it empty). This is a quick way to disable a password for an account. It will set the named account passwordless. User will not able to login.

It is also a good idea to setup user shell to nologin to avoid security related problems:

# usrmod -s /sbin/nologin username

For example to delete password for user johnc, Type:

# passwd -d johnc
# usrmod -s /sbin/nologin johnc