Turn to Twitter, of course. To talk about Facebook. The hashtag "#facebookdown" generated a cascade of tweets, including an image of a T-shirt with the words "I survived #facebookdown." Companies such as Coca-Cola took it as a viral marketing opportunity.
Of course companies that depend on Facebook and Instagram to reach their customers, like the dating app Tinder, had to wait. More than 7,500 websites had services affected by the Facebook outage, according to Web tracking firm DynaTrace.
For most, though, it was just a blip. While Facebook certainly has become an important communications tool for some 1.35 billion people worldwide, a temporary shutdown does not have the same crippling effect as the loss of electricity, water, the Internet or a city's public transit system. It's also a lesson, perhaps, in what happens when we rely heavily on a free service that, while very stable, cannot promise 100 per cent uptime.
"Kind of like the snowstorm that was supposed to cripple New York City, this didn't have much of an impact on Facebook," said Debra Aho Williamson, an analyst with research firm eMarketer. "It was over quickly, it was easily fixed and life came back to normal fairly quickly."
It's possible that companies that rely on Facebook's login tool to let people access their sites and apps lost a "little bit of traffic" or a tiny bit of ad revenue, she said, but it's unlikely to have had a big effect given the brief nature of the outage.
"Life will go on, I think we'll all survive," Williamson said.
At midday in Asia, users of PCs and Facebook's mobile app reported they lost access. Facebook and Instagram also were down simultaneously in the United States, Australia and the U.K. After Facebook was restored, some users reported that the site was loading slowly or not functioning fully. On its website for developers, Facebook said the "major outage" lasted one hour.
Facebook says an internal technical change affected its configuration systems and denied that it was hacked. Lizard Squad, a group notorious for attention-seeking antics online, had claimed responsibility on Twitter for the outages.
Guillermo Lafuente, a security consultant at MWR InfoSecurity, said a technical fault is more plausible than a hack. A denial-of-service attack would have made the sites unreachable rather than accessible with an error message displayed, he said. Facebook's use of multiple data centres also meant an attack on one would have affected one region; this outage was global.
Also, restoring service would be a matter of reversing the technical changes, which matched with the brevity of the outage, LaFuente said.
The temporary loss of service may be Facebook's biggest outage since Sept. 24, 2010, when it was down for about 2.5 hours. Outages were more common in the site's early years, when its backup systems and data centres were not as robust as they are now. These days, the Menlo Park, California-based company routinely tests its infrastructure and sometimes even takes down part of it intentionally to check its resilience.
The outage came a day ahead of Facebook reporting its quarterly earnings.
Lizard Squad on Monday claimed it had defaced the Malaysia Airlines website and would release data from the airline. Its previous hacking claims have been mostly aimed at gaming or media companies such as Sony's PlayStation network and Microsoft's Xbox.
Ortutay contributed from New York.
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