Twitter outage 'due to a problem with a data centre'

Twitter has issued an apology and an explanation of what caused the outage earlier this evening:

We are sorry. Many of you came to Twitter earlier today expecting, well, Twitter.

Instead, between around 8:20am and 9:00am PT [3:20pm and 4:20pm BST], users around the world got zilch from us.

By about 10:25am PT [5:25pm BST], people who came to Twitter finally got what they expected: Twitter.

The cause of today’s outage came from within our data centers.

Data centers 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.

I wish I could say that today’s outage could be explained by the Olympics or even acascading bug.

Instead, it was due to this infrastructural double-whammy.

We are investing aggressively in our systems to avoid this situation in the future.

On behalf of our infrastructure team, we apologise deeply for the interruption you had today.

Now — back to making the service even better and more stable than ever.

– Mazen Rawashdeh, Twitter Vice President, Engineering