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Multiple Sites Down In SF Power Outage
corewtfux writes with word of a major outage apparently centered on 365 Main, a datacenter on the edge of San Francisco's Financial District. Valleywag initially claimed that a drunken person had gotten in and damaged 40 racks, but an update from Technorati's Dave Sifry says the problem is a widespread power outage. Sites affected include Technorati, Netflix (these display nice "We're Dead" pages), Typepad, LiveJournal, Sun.com, and Craigslist (these just time out).
I can verify that it affected much of the Financial District here in SF. We had the power go out 3 times. Seems to be back now. Haven't heard any explanation yet.
It takes Diesel a few years to go bad. That site has fuel polishing systems to prevent that. Because of earthquake risk, they contractually are obliged to have 24-48 hours of backup fuel with many of their clients.
They have the HiTec rotary UPSs in all their facilities, which link a generator to a flywheel UPS. It's stupid to not have backup fuel for that type of system; you can only run for 13 seconds before the load crashes.
It is possible that they got a number of small hits and the generators failed to re-start after a few. Good procedures are to stay on generator until utility stabilizes if you have more than one "hit."
Be interesting to find out what happened.
No kidding. years ago in my former job on traffic systems we had a great UPS with a generator on site and the ability keep it fueled up indefinitely. A security contractor came in on the weekend to install something and tried to wire up a new circuit hot. He slipped with a screwdriver and shorted the white phase to the chasis of the breaker panel. I don't think the tip of the driver actually touched ground, but the burn mark is still there to show how close he got.
The resuting current spike blew the 100A fuses (heavy metal strips) both going in to and out of the UPS. With the UPS effectively broken the generator set failed to start and the system gracefully shut down 40 minutes after the incident. Thats not bad. The batteries were only specified to work long enough for the genny to settle at 50Hz.
In the process of blowing the fuses a spike got back into the power supply of one of our DEC Alphas and took out the power supply. The system was redundant at the software level so I didn't notice immediately.
The UPS guy came out and didn't have enough fuses to replace the blown one, but we found that with a bit of brute force and filing attacks some others could be made to fit.
Please type the word in this image: problems
http://michaelsmith.id.au
For some of these sites they are a lot more central than you might realize. If they failed to build their systems with a secondary site in mind it can be near impossible for the "CTO" types to pony up the dollars for it later. The biggest issue I have seen that affects this is storage. Either they aren't using suitable SAN technologies, or they didn't put enough money behind the storage initiative to set up secondary site replication. I agree with you though. This is a problem that has been solved. Perhaps netflix thought - wth - if we go out for a few hours and people can choose their movies that's just tough luck.
Sun.com going down is a good example of someone totally screwing up. They have absolutely NO excuse. The others - maybe they can get away with it and we won't care. If Sun can't keep their own site up, how can I expect them to keep mine up?
...until the commercial power fails and doesn't come back for days.
:o(
The only places I've actually seen the insane levels of backup that some would like is in some telco central offices. The one I was associated with the longest had eight-hour-plus battery backup and 8 days of fuel for the diesels. Some of our really remote microwave sites had 24 hour battery and 30 day diesel.
Of course one of those sites failed high up in a mountain range in a mid-winter storm (Tieton, 1978) when the commercial power failed, and the starter battery for the diesel froze. When one of the techs finally got there (after burying his Sno-Cat and walking the last couple miles), he had to chip ice off the steel door to get inside, where he was able to get the diesel started with a little "rewire" of one of the backup battery sets. Oh, his two-way radio also failed during his hike, since it was outside his snowsuit, and the lack of communication caused the company to start two more Sno-Cats and a helicopter in that direction.
The site was out for nearly six hours, IIRC.
Even the BEST designs are subject to failure.
--
Tomas
And this was in addition to the 48VDC battery backup.
In the entire history of electromechanical switching in the Bell System, no central office was ever down for more than 30 minutes for any reason other than a natural disaster. That record has not been maintained in the computer era.
If you have to build reliable systems, it's worth understanding electromechanical telephone switching. Because the components weren't that reliable, the systems had to be engineered so that the system as a whole was far more reliable than the components. Read up on Number Five Crossbar. The Wikipedia article isn't really enough to understand the architecture, but other references are available.