[Spacewalk-list] Understanding scheduling

[Tomas Lestach]

> Good day,
> 
> 
> Just a quick question on how the scheduling works.
> By default, the client checks in every 4 hours - let's assume that
> value is unchanged.
> 
> 
> Consider the following scenario:
> 
> 
> The machine checks in at 7am - nothing to do.
> At 8am I schedule a package installation for anytime after 1pm.
> At 11am the client checks in again, a future event exists.
> 
> 
> Would the client grab the task and execute it at (or around) 1pm, or
> would it only execute the task after the first check-in after the
> scheduled point, in this example, 3pm?

Good question.

Well theoretically - what the client could do, is it would notice there's a future event at 1pm. The client would need to run
rhn_check at 1pm (to make sure the event wasn't deleted in the mean time). But that would mean, if you'd schedule
the event for 10000 systems, your spacewalk would need to handle 10000 rhn_check calls at 1pm, what it obviously couldn't handle.
And this is exactly the situation we need to avoid.

So, the answer to your question is most probably clear now - the task would be executed by the first check-in after 3pm.

But, in case you enabled 'staging content' for your organization,
WebUI - Admin - Organizations - <your org> - Configuration
the client should be able to pre-download the rpms needed for any future install action
and just install them with the rhn-check after 1pm. See 
https://www.redhat.com/archives/spacewalk-devel/2010-July/002835.html
for more info.

Regards,
--
Tomas Lestach
Red Hat Satellite Engineering, Red Hat