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I was wondering if the battery supplies energy for the whole system or
just the mainboard. If you check the cables, the hard-drives are still
12V+5V powered. Do you think that they just run without swap and if
power fails they just announce that nodes is going down and dies? Do
you prefer thinking that the power source has even more modifications
and it continues supplying 12+5V to the drives and keeps the whole
system running for a few minutes?<br>
I don't where to put my money......<br>
<br>
regards<br>
<br>
ariel<br>
<br>
David Mathog escribió:
<blockquote cite="mid:E1Lpm2C-0004CM-8y@mendel.bio.caltech.edu"
type="cite">
<pre wrap="">Nifty Tom Mitchell <a class="moz-txt-link-rfc2396E" href="mailto:niftyompi@niftyegg.com"><niftyompi@niftyegg.com></a> wrote
</pre>
<blockquote type="cite">
<pre wrap="">I suspect that the UPS component is very short. i.e. finish the current
search, notify the distributed google world that the 'node' is going
off line and then go off line. I doubt that the specifications for the
UPS are hours or days the way a national weather center or hospital data
center or other critical resource is specified. If someone post a pool
for the UPS time factor put me down for 15min.
</pre>
</blockquote>
<pre wrap=""><!---->
Pretty much what I was thinking too.
In the picture on the OP's link the external PS does not look any bigger
than a standard unit, which leaves very little room in it for the UPS
battery. The primary purpose of the UPS is most likely just to give
them a few minutes leeway to turn on the data center's generators when
the main power fails. Even a couple of minutes UPS coverage is plenty
to allow them to save significant money on the backup
generators/failover circuitry. Also, a smaller battery wouldn't have
the weight penalties of the sorts of sealed lead acid batteries usually
found in a UPS. And there could be some other advantages, for instance,
they could throw the main breaker on a rack (assuming it is wired that
way), move the common plug from one circuit to another, and then close
the breaker again, all without losing service. Big central UPS units
don't provide that sort of flexibility.
Regards,
David Mathog
<a class="moz-txt-link-abbreviated" href="mailto:mathog@caltech.edu">mathog@caltech.edu</a>
Manager, Sequence Analysis Facility, Biology Division, Caltech
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