Shutdown - why does it work?

I've been having trouble with scheduled shutdown in Debian 10 and i've lost track of how it works.
As far as i understand /sbin/shutdown now points to systemctl. I can't execute ´shutdown´ even when using the su command though /sbin is set as part of roots PATH in /etc/profile

if [ "`id -u`" -eq 0 ]; then
  PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"
else
  PATH="/usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games"
fi

Shouldn't this make it available for root at least?
However i made a script for scheduled shutdown using ´systemctl poweroff´ directly
The script does what it's intended to do without any further authentication when logged in locally. When logged in via ssh i get:

<user>@debian:~$ ./pc-shutdown.sh 0
<user>@debian:~$ Failed to set wall message, ignoring: Interactive authentication required.
Failed to power off system via logind: Interactive authentication required.
Failed to start poweroff.target: Interactive authentication required.
See system logs and 'systemctl status poweroff.target' for details.

´systemctl poweroff´ istelf works without password locally and needs two authentications when logged in via ssh, Once for a wall message then for systemctl poweroff.
I wonder why the script works without privileges when logged in locally in the first place.

Without seeing what's inside pc-shutdown.sh, I can't say much. Obviously, systemctl wants authentication as root, i.e. the root password.

Are you sure that systemctl poweroff works without password when called from a nonprivileged user?

Originally Posted by berndbausch Without seeing what's inside pc-shutdown.sh, I can't say much. Obviously, systemctl wants authentication as root, i.e. the root password. Are you sure that systemctl poweroff works without password when called from a nonprivileged user?

I just tested it again, systemctl poweroff works without sudo or any other authentication when logged into the terminal-app on tty7 as on any other tty as unprivileged user.
The script goes:

(
sleep $1
systemctl poweroff
)&

wich chmod 755

probably: https://unix.stackexchange.com/quest...-systemctl-pow
this is a policy setting

Originally Posted by pan64 probably: https://unix.stackexchange.com/quest...-systemctl-pow this is a policy setting

That explains the unprivileged execution. But why the password-prompt when logged in remotely?

Shutdown works as expected on my Debian systems, both Buster and Sid. I haven't tried systemctl poweroff.