LaoBlog

Since Kubuntu 15.04 provides a new login manager, called sddm, as usual only logins above a certain ID (1000) is permitted. There are scenarios when you want to login in a graphical environment using the root account. Although many complains it is not the right thing to do, the pc is yours, and you have the right to do what you want. Therefore here I show you haw to enable root login on Sddm. I assume you know what you're doing, I don't take any responsibility if after following this Howto you can't login anymore!

I assume you've already set up a password for the root account.

First at all, you need to modify /etc/sddm.conf as following:

auth    required        pam_succeed_if.so user != root nopasswdlogin

so that it'll look like:

#auth    required        pam_succeed_if.so user != root nopasswdlogin

Then uncomment

# auth    sufficient      pam_succeed_if.so user ingroup nopasswdlogin

so that it'll become

auth    sufficient      pam_succeed_if.so user ingroup nopasswdlogin