An internal "cascading bug" is said to be responsible for Twitter's largest-ever outage, not an external hack as claimed. A hacking group called Ugnazi claimed in emails to several organisations to have caused the outage. The group has given no credible explanation of how it did so, though, and Twitter was quick to dismiss the claim.
Unable to send their 140-characters-or-less messages, many were left twisting their hands. Many went to Facebook for a social-media fix. More than 140 million active Twitter users bombard the site with 340 million tweets a day via the Web, smartphones, tablets and computers. As Twitter came back up, #WhenTwitterWentDown became a top 10 trending topic on the site. It was created in March 2006 by Jack Dorsey and launched that July.
The service was down in the U.S. and other parts of the world. In the U.S., Twitter came back up about 70 minutes later only to suffer at least two subsequent outages, according to online monitoring firm Pingdom, based in Stockholm.
"Twitter's Web site has had more downtime today than it had the entire year to date before today," says Pingdom analyst Peter Alguacil said Thursday.
Mazen Rawashdeh, vice president of engineering, on the company's blog said, "It's imperative that we remain available around the world, and (Thursday) we stumbled."
Outages are not unusual for Twitter. "Usually, it's an overcapacity issue, but occasionally it's some other technical problem," says Shelly Palmer, author of Overcoming the Digital Divide.
"When it fails," Palmer says, "it shuts off thousands of dedicated, live news feeds to literally millions of people."