[Beowulf] Remote console management

[David Mathog]

> > Those power strips are relatively expensive, but as a way
> > to remotely force a boot on a node they are cheaper per
> > node than the IPMI cards.
> 
> We're going to get the IPMI cards anyway for some of the other features. 
> Since we can use IPMI to hard/soft power up/down I don't see the need to 
> also have the power strips.

I do.

I've often seen our Tyan boards go into a state where
they IGNORE the front panel reset and power buttons.  The IPMI
cards I'm aware of, for instance this one:

http://www.supermicro.com/products/accessories/addon/AOC-IPMI20-E.cfm

control power through the same headers as the buttons on
the chassis: much as I described in another part of
this thread concerning wiring these motherboard
pins out the back.  So if your motherboard goes into one of these
nonresponsive states you will _not_ be able to reboot it with
the IPMI card.  However, you _could_ reboot it by actually
cycling the power going into the box via the remotely controlled
power strips.

There may be IPMI cards which have a socket for the PS
cable, and another power cable from there to your motherboard,
so that they can gain access to the control lines between the PS
and the motherboard.  However, I've never encountered such a beast.

Regards,

David Mathog
mathog at caltech.edu
Manager, Sequence Analysis Facility, Biology Division, Caltech