[Beowulf]Infrastruture planning for small HPC 40/100 gigabyet eyhernet or Infiniband?

Nifty niftyompi Mitch niftyompi at niftyegg.com
Sun Jul 27 16:51:38 PDT 2008

On Sun, Jul 27, 2008 at 09:28:07PM +0200, Eugen Leitl wrote:
> On Sat, Jul 26, 2008 at 09:15:23PM -0700, Nifty niftyompi Mitch wrote:
> > Did I read this correctly? 
> > Are you cutting holes in the walls of a home.....?
> Real homes have cable ducts -- I'm limited to drilling through walls.
> Unfortunately, due to lousy electric installation I'm stuck with 
> severe ground loop issues (I catched that too late orelse
> I would have put in a heavy ground wire strung along the CAT 6/7). 
> Galvanic separation would be a god-send -- but for the price 
> tag, and unavailability of GBit polymer optical.
> CAT 6 is great, except if you see sparks when plugging in RJ-45s.
> Also, most systems tend to shutdown spontaneously overnight when
> on such dirty network.
> > Also all wires in the wall MUST be safety rated for such use.

OK if you have severe ground loop issues you must rethink
what you are doing!   Ground loops generated by a bad power
install can have almost unlimited currents and present
a serious fire hazard.  Get the problem fixed.

Contact a qualified electrician and find out what the root cause is.
AFAIK most network switches do provide MAC level isolation at the physical 
layer so I am confused and _concerned_ about your comment about seeing sparks
at the RJ-46.   Get the problem addressed promptly.

	T o m  M i t c h e l l 
	Looking for a place to hang my hat.

More information about the Beowulf mailing list