On 26Oct2018 03:10, Patrick Dupre <pdupre(a)gmx.com> wrote:
> On 10/25/18 4:55 PM, Patrick Dupre wrote:
> > On Thu, Oct 25, 2018 at 10:40 AM Patrick Dupre <pdupre(a)gmx.com
> > <mailto:pdupre@gmx.com>> wrote:
> > I do not understand this error message:
> > /sbin/shutdown -h +70
> > Failed to set wall message, ignoring: Interactive authentication
> > required.
> > Failed to call ScheduleShutdown in logind, proceeding with immediate
> > shutdown: Interactive authentication required.
> >
> > Did you run it as root or with sudo?
> >
> > In visudo, I have
> > pdupre localhost=/sbin/shutdown -h +70
>
> That wasn't the question. Did you "sudo /sbin/shutdown -h +70" or did
> you simply run it as yourself ("/sbin/shutdown -h +70")?
>
> If the latter, you're not root (nor are you sudo'd to root). Both
> wall messages to all users (the first message) and shutdown (the second
> message) can only be done by someone with root privileges. If a normal
> user tries either, they must authenticate and they must be members of
> the "wheel" group (admins).
Really!!
Here is my understanding.
The setting of visudo also the user pdupre to run the line command without being root.
(just /sbin/shutdown -h 70)
This is incorrect. The visudo line says you may _use sudo_ to invoke
shutdown as root.
Actually, in 90% of the cases the line command works without complain,
but sometimes
it does not work and I do not understand why.
We'd need to see the complaint. But maybe shutdown itself has a list of
users (probably via a group) who may run it? See "man shutdown" to find
out. It should say.
Cheers,
Cameron Simpson <cs(a)cskk.id.au>