Amazon failed diesel generators



Amazon explained why the blackout of the data center in the region of East-1 in Northern Virginia, bringing the June 30 gone offline Instagram, Netflix, Pinterest and other sites.

The reason he called incorrect operation of diesel generators, specifically, raspredelitelno flap (switchboard), which was to switch the system from one channel to another. After the jump voltage "generators start normally", but if one data center East-1 powered from generators without incident, the second data center, "each generator separately, could not provide stable voltage after you run them," explains Amazon. As a result, the network is not automatically switched to the power from the generators, and UPS'Ah soon ran out of charge.

Diesel generators were installed in the data center in late 2010 and early 2011, prior to the installation they were tested by the manufacturer. After installation in the data center they again drove through eight hours of tests, everything worked fine. May 12, these diesel generators were again tested in the field, when the underlying supply of the data center completely off, too, everything was fine.

Now the generators will undergo repairs and re-certified by the manufacturer or they are replaced by others. Amazon promises to make every effort so that a similar situation is not repeated in the future: will increase the window time which is given on the diesel generators to increase power to reach a stable voltage before the automatic system decides to switch on power from the alternator or not. In addition, data centers will increase the number of engineering personnel to the power outage they are in case you need to manually start the generator and switch the system powered by it, so UPS'you will not be able to discharge and clients of the data center will suffer.

via Wired
Article based on information from habrahabr.ru

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