SLES and openSUSE by default set to automatically log in user without authenticating with username and password. While convenient, this is a security risk as anyone with physical access to the system could boot it up and access the default user's account.
The option to enable automatic login is set up during the system's installation. You can, however, disable automatic login in SUSE via YaST or the command line at any time.
Methods to disable automatic user login in openSUSE and SLES:
> sudo nano /etc/sysconfig/displaymanager
## Type: string ## Default: # # Define the user whom should get logged in without request. If string # is empty, display standard login dialog. # DISPLAYMANAGER_AUTOLOGIN="user"
DISPLAYMANAGER_AUTOLOGIN=""
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