Dennis Clarke wrote: > Nothing can replace batteries. The more the better. > Most power solutions should grant at *least* 30 minutes on battery and if > not then I would not host my gear there. I just finished installing a 45 > minute battery runtime solution with 16,000 VA of power. It is not that > costly really to stick in an APC Symmetra SY16K unit when one looks at the > cost of downtime.
Most datacenters consume a *lot* of power. Just how many lead-acid batteries can you fit in one building? (There are probably safety and weight issues, plus density problems if every other rack in your datacenter is a UPS). And in any case, an outage can just as easily last an hour or more as it can last a few minutes. So the usual plan is that the UPS only needs to last long enough for the generator to kick in, e.g. 5-10 minutes. I've also seen people use flywheels for short term power, but again there's only so large a flywheel the authorities will let you install. Hugh. PS: at an Indian office of the company I work for, we recently managed to have a backup generator last for 2-3 days via continuous refueling because of the failure and wait-for-replacement of a step down transformer. I doubt you could have had enough batteries for this... _______________________________________________ opensolaris-discuss mailing list opensolaris-discuss@opensolaris.org
