Twitter has blamed yesterday’s outage on a dual data centre failure.
The popular social network site went down yesterday afternoon UK time and was out of action for around two hours. Users were greeted with a rather baffling error message:
There was speculation that the outage had been caused by Olympics overload, with the crash coming just the day before the opening ceremony for the London 2012 Games.
However in a blog post the company said Olympic fever was not the cause. Instead and fault in one data centre was compounded by a fault at another that was supposed to provide back up.
"The cause of today’s outage came from within our data centres, "Mazen Rawashdeh, VP, engineering, explained. "Data centres are designed to be redundant: when one system fails (as everything does at one time or another), a parallel system takes over. What was noteworthy about today’s outage was the coincidental failure of two parallel systems at nearly the same time. "
Rawashdeh added that Twitter is "investing aggressively" is its systems to stop this sort of "infrastructural double-whammy" from happening again.
It is the second time in a matter of week the site had experienced issues. In late June Twitter.com was inaccessible for many users, both mobile and web-based. The company blamed that on a "cascading bug", where a bug in one piece of software has a knock-on effect on others software.
After that outage Rawashdeh said Twitter had been experiencing very high uptime. "For the past six months, we’ve enjoyed our highest marks for site reliability and stability ever: at least 99.96% and often 99.99%. In simpler terms, this means that in an average 24-hour period, twitter.com has been stable and available to everyone for roughly 23 hours, 59 minutes and 40-ish seconds."
