[Beowulf] Green Cluster?

[Huw Lynes]

On Sun, 2008-07-20 at 21:20 -0400, Joe Landman wrote:
> Greg Lindahl wrote:

> That said, we like IPMI in general, and even better when it works :( 
> Sometimes it does go south, in a hurry (gets into a strange state).  In 
> which case, removing power is the only option.

Agreed. Currently my most common reason for going into the machine room
is to pull the power cable out of a node in the hope that the BMC will
reset in a sane state, which it usually does. If I had network switched
PDUs I'd never have to leave my office. 

The advantage of smart PDUs is that they can switch off anything whereas
IPMI and other lights-out systems usually only exist on computers. All
things being equal I'd rather have both.

There is also a green issue here. Modern systems draw power even when
they are "off" in order to keep the BMC and network card live. Obviously
a system switched off at the PDU draws no power. Having said that I
haven't looked at how much power an unloaded smart PDU draws.

Thanks,
Huw  

-- 
Huw Lynes                       | Advanced Research Computing
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