[rescue] Sun T5240 power supply failure?

[Arno Kletzander]

Peter Stokes <peter at ashlyn.co.uk> wrote:
> Not really talking about different things.
> 
> The 3000 has the ability to have two PPS (Peripheral Power Supplies). The base
> system comes with just one which also has the mains inlet connector and
> switch, p/n is 300-1307 or 300-1400. The 300-1301 was an optional second
> backup PPS which you correctly say was used in the other EXX00 systems. If you
> open up the 300-1301 and the 300-1307 you will find the same board and can
> convert between the two, I have done this several times.

Ah, now I see. That also explains the odd shape of the PCB inside the 1301.
Now you've got me wondering why Sun didn't decide to go the whole redundancy/
high availability hog and put in _two_ 1307/1400 style modules. (As it is, if
the Inlet module PPS0 fails, the system will continue to run on the PPS1 for
now, but ultimately will have to be shut down to be able to replace the PPS0!) 

Just taking two Inlet Modules and sticking them in one chassis probably is a
REALLY STUPID idea (if not impossible because of the case panel), as AC mains 
is most probably just bussed internally between the two slots, meaning you're 
going to end up with exposed connector parts live, shorts if cables are plugged
into different circuits or backwards, and maybe other unfavourable events. It
would be imperative to implement some kind of isolation and failover logic to
make that work safely. Then again, it would remove the inlet module, circuit
(and, if present, UPS) as Single Points of Failure.

adh at an.bradford.ma.us (Sandwich Maker) wrote:
> i've always thought that while fc/25 was sun's own, the gbics - the
> plug-in fiber r/t modules - were standard.  if true, many brands could
> find their way under sun covers over the years.  iirc you can get
> copper gbics, for situations which don't demand the distance fiber can
> cover.
> 
> in my own encounter with a sun ssa [in a y2k project] i learned from a
> sun fse that the original ssa gbics were prone to failure, as he
> replaced ours.  i may have gleaned the above gbic intel from him.

That's my understanding as well, but - those FC/25 modules used there do
not come in the usual GBIC form factor (closed matchbox shaped thingie 
with subminiature Amphenol connector on one end and fiber Transmitter/
Receiver on the other) but are PCB modules that piggy-back onto an sbus
card or system planar with a perpendicular 4*10(?) header. So it looks 
like _that_ interface (for which I don't even know a name) must have been
a standard in its own right.

Arno