CentOS - Sep 2015 - CentOS-6.7 Passing delayed shutdown via ssh command line argument?

If I log into a host via ssh from my workstation then I can enter this:

shutdown -r +90&

and log out.  The shutdown command will continue in effect and will
activae 90 minutes later.

However, if I do this instead:

ssh -t host.domain.tld 'shutdown -r +90&'

then the shutdown command does not remain in effect.  Why is this so
and is there some way to achieve this?


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James B. Byrne                mailto:ByrneJB at Harte-Lyne.ca
Harte & Lyne Limited          http://www.harte-lyne.ca
9 Brockley Drive              vox: +1 905 561 1241
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Canada  L8E 3C3

In article <f90407e5ac62949cab27d3bda74faa74.squirrel at
webmail.harte-lyne.ca>,
James B. Byrne <byrnejb at harte-lyne.ca> wrote:
> If I log into a host via ssh from my workstation then I can enter this:
> 
> shutdown -r +90&
> 
> and log out.  The shutdown command will continue in effect and will
> activae 90 minutes later.
> 
> However, if I do this instead:
> 
> ssh -t host.domain.tld 'shutdown -r +90&'
> 
> then the shutdown command does not remain in effect.  Why is this so
> and is there some way to achieve this?
I think shutdown receives a HUP signal when the connection is terminated,
because it still has the ssh tty as its controlling terminal.

I've just done some experimenting using sleep instead of shutdown, and
found this:
- you need to omit the -t
- you need to redirect stdin/stdout/stderr

So try:

ssh host.domain.tld 'shutdown -r +90 </dev/null >/dev/null 2>&1
&'

Cheers
Tony
-- 
Tony Mountifield
Work: tony at softins.co.uk - http://www.softins.co.uk
Play: tony at mountifield.org - http://tony.mountifield.org

On Wed, September 30, 2015 09:33, James B. Byrne wrote:
> If I log into a host via ssh from my workstation then I can enter
> this:
>
> shutdown -r +90&
>
> and log out.  The shutdown command will continue in effect and will
> activae 90 minutes later.
>
> However, if I do this instead:
>
> ssh -t host.domain.tld 'shutdown -r +90&'
>
> then the shutdown command does not remain in effect.  Why is this so
> and is there some way to achieve this?
>
>
Why is it that after beating my brains out and finally asking for help
the answer appears?  I have to close the stdxxx files before putting
shutdown into the background.

This seems to work:

ssh host.domain.tld 'shutdown -r +90 > /var/log/shutdown_$(date
+%Y%m%dT%H%M).log  2>&1  <&- &'



-- 
***          e-Mail is NOT a SECURE channel          ***
        Do NOT transmit sensitive data via e-Mail
James B. Byrne                mailto:ByrneJB at Harte-Lyne.ca
Harte & Lyne Limited          http://www.harte-lyne.ca
9 Brockley Drive              vox: +1 905 561 1241
Hamilton, Ontario             fax: +1 905 561 0757
Canada  L8E 3C3

man nohup