Re: [cobalt-users] Cobalt Raq's and UPS.

[Malcolm McLeary <mmcleary@xxxxxxx>]

Hi Bruce,

on 12/3/02 2:52 PM, Bruce Timberlake <bruce.timberlake@xxxxxxx> wrote:

>> What about UPS for Qube3?
> 
> No "support" was pre-included on Qube like on the RaQ.  UPS-supplied
> software _should_ work the same on Qube as it would on RaQ.  There's
> just no master/slave notification/etc like on RaQs...

Actually some slave software would be cool.  It might be better to install a
better UPS which has network comms builtin and tells the Qube3 to shutdown
via TCP/IP instead of a serial cable.  Then you could connect the serial or
USB cable to a Mac or PC so you can manage the UPS.

>>> That's all there is to it - plug the RaQ into the UPS, and connect the
>>> serial cable from the UPS to the 2nd serial port on the RaQ.  Then
>>> install the UPS software (it did come with some, right?) on the RaQ.
>>> Voila.
>> 
>> Actually I don't think its quite that simple.
> 
> It never is, is it?  :)
> 
> I have not actually set up a UPS on a RaQ, but during my training when
> starting at Cobalt several eons ago (Feb 2000 to be exact), that is how
> the process was explained to me by someone in the support or engineering
> group.  I had no reason to doubt them at the time, and have not been
> able to requisition a UPS of my own from Sun's internal supply to
> validate on my own.
> 
> If I have put out incorrect/incomplete info, I apologize.  Hopefully,
> when/if the KB "how to" gets written, that will put and end to the
> confusion...

I don't think you said anything wrong ... just made it sound easy.  ;-)

>>>>> More specifically how do you force the Raq to shut down when
>>>>> the supply is minutes away from discharge ? is it script based?
>>>>> does it have this script already buried away somewhere in the box?
>>>> 
>>>> I think it is another one of those cobalt features we bought, and
>>>> does not work. I never could get mine to work
>>> 
>>> Generally, a UPS (APC specifically that I know of) will come with
>>> software (PowerChute?) that loads on the server and talks to the UPS via
>>> serial cable (thus the 2nd serial port on the RaQs).  That 3rd party
>>> software from the UPS manufacturer is what actually handles the server
>>> shutdown, etc.
>> 
>> From what I've seen the APC Linux software is unsupported,
> 
> Unsupported by Sun Cobalt, yes (we _are_ talking 3rd party software
> here! ;^) ) Is it also unsupported by APC??

To the best of my knowledge the APC software is unsupported by APC ... its
not really theirs ... its just available on their web site and supposed to
work.

>> VERY basic and requires a special cable not normally supplied.
> 
> Hm. I haven't messed with an APC UPS in a couple of years, so I'm
> admittedly weak there, but I could swear my APCs came with the cable.
> Could it just be a null-modem cable??

I'm led to believe that its REALLY simple ... no traditional communications
(bits, baud, etc), just a pin going hi or low depending on if mains is
present.

>> One issue I have not seen dealt with is the case where the the UPS tells the
>> Linux Appliance to shutdown and then power is returned.  The Linux Appliance
>> continues to shutdown and sits there waiting to be powered down.
>> 
>> What is needed is a way to get the UPS to actually remove power from the
>> Linux Appliance so that when power resumes it actually comes back up.
> 
> Yes, this is the problem with a "hard" power switch like RaQ3/4 have.
> Using the ATX-style motherboard like XTR does enables "soft" power
> control, and the appliance _does_ actually power down when the shutdown
> command completes.

Thats nice.  ;-)

But to get it to restart don't you still need the power to cycle off an on?

>> The ONLY situation which works is to hope for a power disruption longer than
>> the UPS battery lasts or use the UPS only as a temporary power source while
>> backup power is brought online.  In this case the UPS doesn't need to talk
>> to the Linux Appliance at all.
> 
> Well, an orderly shutdown is still preferred if possible, and this is
> what you would get with the UPS connected and talking to the RaQ...

Orderly shutdown is what we want, but we also want restart.  What I meant
was that after the display says "Power me down now" ... you hope the battery
runs out so when the power comes back the device will start again.

Alternatively, the UPS needs to be programmed such that after ordering a
shutdown it waits x minutes then removes the power from the device.  It then
waits for power to resume before providing power to the device again.  This
way even devices with hard power switches can be orderly shutdown and then
restarted.

Even then its not that simple as its possible for a power disruption to
occur while the device is starting so it might miss the shutdown command.

>>> Otherwise, you'd have to get some sort of battery charge monitoring
>>> script to work across the serial connection (would probably vary vendor
>>> to vendor, thus the lack of inclusion of a set way to do it from us),
>>> and initiate a "shutdown -h now" if the battery is below your threshold
>>> charge level...
>> 
>> Have a look at what MGE have to offer, however everyone seems to be moving
>> towards using USB instead of serial and I'm under the impression that the
>> USB socket on Cobalt Linux Appliances is just there for show ... its not
>> actually supported ... or its intended for future use.
> 
> The 2.2 kernel we supply does not have USB support enabled.  There was
> some rudimentary USB support for some devices (printers, etc) in 2.2.x,
> but the bulk of USB support came with 2.4.x.  When/if a 2.4.x kernel is
> released for the RaQ3/4 line, the USB port will work.

Cool, but I guess holding one breath is pointless.

> I will pass the USB UPS support idea to the RaQ PM for consideration on
> future RaQ systems and/or backport to existing RaQ systems...

As I said above I'd prefer "slave" software which is compatible with UPSes
with their own builtin "master".  Some of these UPSes are managed via a
builtin web server ... a really nice "fit" with Cobalt appliances.

Cheers,  Malcolm