You are not asked for superuser privileges, but “reboot” is not found, therefore the command-not-found script is run, which does find it in /sbin/ and prints that informational message. (at least I guess this is happening… )
> I do not see your fear for su -. First log in in the CLI as a normal
> user and then use su - to login as root. That is the rule of caution.
No, login in directly in the CLI directly as root is perfectly correct,
the extra step of entering as user, then suing, is not necessary.
It is different when doing it in a graphical terminal because then you
want to avoid everything else running as root as well.
It is also different when using a remote session, because typically
remote login as root is disabled; if it were not, attackers can do a
dictionary attack against the known user name, root. If they have to
guess the user, it is way more difficult.
But when using the text none of those limitations apply. There is no
network access, and only one user task is running as root. When you
finally do the “su -”, you have the exact same powers. Besides, login as
user then suing means that home has to be mounted and used, which is a
dificulty for doing maintenance as root sometimes.
Cheers / Saludos,
Carlos E. R.
(from 12.3 x86_64 “Dartmouth” at Telcontar)
Your assumption is that this is a login at the real console of the system. Then you are correct that a direct login might be needed. And you are also correct then that is rather secure (eexcept for people standing behind you or using morrors).
But I have nowhere read above that that is the case for the OP. He only says he loged in as root. For me this leaves open: login in the GUI and remote login in GUI or CLI