The BBC's controller of digital distribution has revealed just what made the whole of BBC Online go, well, offline.
In a blog, he said about the blackout: "[There] was a failure in the systems that perform two functions. The first is the aggregation of network traffic from the BBC's hosting centres to the internet.
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"The second is the announcement of 'routes' onto the internet that allows BBC Online to be 'found.' With both of these having failed, we really were down!"
The BBC has apologised after all of its websites went down yesterday, due to a massive technical fault with its network.
It's a rare thing for the BBC's entire internet infrastructure to fail, so Twitter was flooded with people unsure just why none of the Beeb's websites were working from 11pm till 12am.
Some conspiracy theorists speculated that it was a DDoS attack by Anonymous, while others thought it may have something to do with the recent cuts announced within the BBC's online sector.
Steve Herrmann, editor of the BBC news website, tried to quash the rumours with a blog post, explaining it was a 'major technical fault' that caused the outage.
"It's not often we get a message from the BBC's technical support teams saying, 'Total outage of all BBC websites'," said Herrmann.
"But for getting on for an hour this evening, until just before midnight, that's what happened. We haven't yet had a full technical debrief, but it's clear it was a major network problem.
"We'd like to apologise to everyone who couldn't get onto the BBC News website during that time."
The last BBC blackout outage of note was in August 2010, when the BBC.co.uk homepage was offline for just 15 minutes.
With so many eyes on the BBC, this also caused mass panic on social networks.
Amazingly Twitter didn't melt last night, as the entire BBC network took a whole hour to get back up and running.