[Nut-upsdev] Joining forces with the Network UPS Tools

[Arnaud Quette]

2008/10/5 Arjen de Korte <nut+devel at de-korte.org>:
> Citeren Arjen de Korte <nut+devel at de-korte.org>:
>
>>> - We could manage a full power chain of UPSs and RPCs, and add some
>>> smarter/advanced features (like subscribing clients (nut slaves
>>> installed on computers) on a specific outlet, and have these shutdown
>>> earlier than others before putting the outlet off)
>>
>> I'm not sure what you're trying to accomplish here. Why would clients
>> subscribe to a specific outlet? And why would we want to switch off an
>> outlet early?

there are several use cases for the early shutdown of a specific outlet:
- getting some more runtime for critical systems, when the power
failure last longer that expected.
- remote management of some devices (either for cycling a load, or
simply not to waste energy)
...

>> We already have 'upssched' to shutdown clients early, so the only load
>> saving that would benefit from shutdown through the outlet switches
>> are 'dumb' devices that don't run NUT client software or NUT clients
>> that somehow are no longer responsive. In both cases, they will be
>> shutdown 'hard' anyway and as far as I can see there is little you can
>> do about it.
>
> Never mind, I already figured out a usage. If one of the machines connected
> to an outlet gets stuck and you want to cycle the power on that outlet
> (probably the main reason to use RPC's in the first place) you want to bring
> down the other systems on that outlet down cleanly. Shutting down the whole
> UPS/RPC system is currently the only option and this could be made more fine
> grained.

that's 1 of the 2 main use cases here.
the other being that upsmon could monitor
outlet.X.autoswitch.charge.low (where X is the outlet on which we
subscribed the slave) against battery.charge to launch the shutdown
without the need of upssched.

Arnaud
-- 
Linux / Unix Expert R&D - MGE Office Protection Systems - http://www.mgeops.com
Network UPS Tools (NUT) Project Leader - http://www.networkupstools.org/
Debian Developer - http://people.debian.org/~aquette/
Free Software Developer - http://arnaud.quette.free.fr/