John Bushnell <john.bushn...@icb.ucsb.edu> wrote: > Another reason for not having UPS power for an entire cluster is > cooling. In our server room, if we lose regular power, we lose our > large AC units as well. So we need to be careful what we keep plugged > into our emergency power circuits (a relatively tiny amount of > equipment). Having an entire stack of nodes churning away during a > power outage would kill us pretty quickly.
Excellent point. Like most cooling on campus, the AC in my machine room dumps heat into chilled water lines. Eventually that heat is transferred from the water to the atmosphere at a cooling tower several hundred meters away in the central plant. I don't know if central plant has a backup generator to circulate and cool the water. Assuming not, even if this machine room had a UPS big enough to keep everything running, including the fans on the AC unit, there would still be no way to cool the room. Even if a backup generator is present at the central facility, I am pretty sure the powers that be would prefer the machine rooms turn off during the power outage, so that whatever cooling capacity remains may be used for more critical tasks. For instance, keeping cold rooms and animal facilities at safe temperatures. Regards, David Mathog mat...@caltech.edu Manager, Sequence Analysis Facility, Biology Division, Caltech _______________________________________________ Beowulf mailing list, Beowulf@beowulf.org sponsored by Penguin Computing To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf
