[CentOS] C8 Question

Fri Jan 24 14:44:42 UTC 2020
Pete Biggs <pete at biggs.org.uk>

> I noticed a strange behaviour (don't know if this is the wanted 
> default). If I try ,from normal user shell, to run command like "reboot" 
> or "shutdown -h now" system will reboot/shutdown. This happens on tty 
> console, on xfce terminal and ssh session.

I've just created a normal user on my test system and when I try to
reboot or halt the system when logged in via ssh I get:

   $ reboot
   Failed to set wall message, ignoring: Interactive authentication required.
   Failed to reboot system via logind: Interactive authentication required.
   Failed to open initctl fifo: Permission denied
   Failed to talk to init daemon.

Which is correct behaviour.

However, a user logged in at the machine as GUI console session has
always been able to halt or reboot the system.

> Why on CentOS a normal user can shutdown the system without root 
> privileges? I think that on any server normal user should not be able to 
> shutdown the system without privileges.
If it's a desktop machine, then the console logged in user should be
able to shutdown the machine - at least then it means they don't resort
to pulling the plug.  Presumably you don't allow users physically near
a server?