How to block the root user login in system direct console. Users should login with non-root ids themselves and then use the su command to become root. Which configuration file i need to check and disable it.
There seems to be some fundamental misunderstanding: the "console" is a directly attached terminal which is used for emergencies (like network connections being all down and the like).
As you use it in cases of emergency only and you can easily physically protect it (it is perhaps in the immediate vicinity of the system itself) you don't want to hinder roots access via this terminal. You would only unnecessarily complicate your work in cases of emergency.
bakunin
if you want to disable ssh login
than in sshd_config file add this line
PermitRootLogin no
Still not sure that this is such a great idea - the virtual only time I ever use direct console access to any of my lpars is because scsu (or even a normal userlogin) does not work. Via console I do not have to do that so I can fix my problem ... if you really want a securized root than you might rather want to put the password into a virtual save where you need additional approval to get it, than forbid direct login - our root password is in a virtual safe and changed each time it had been used ...
Regards
zxmaus
this might work. you can also limit which users can su with the sugroups attribute
chuser -a login=false root
chuser -a rlogin=false root