Today a lot of Twitter users found themselves unable to access their tweets and retweet their friends after Twitter suffered a bug that caused it to become intermittently inaccessible to their users. The fail whale once again reared its albino head with a huge splashdown starting at around 12pm ET and it affected almost all of its systems.

After some bug wrangling the staff got the social media giant steaming along again by 2:10pm ET; but aftershocks continued to cause the site issues for a few hours after that.

According to a blog post over at Twitter what awoke the fail whale from its dreamless slumber was a “cascading bug,” or a systems-wide malfunction that manifests itself by affecting more than just one element of the entire system. Seeing as how Twitter lost its website and almost its entire suite of APIs, this would appear to be very true-to-fact.

Mazen Rawashdeh, Twitter VP of Engineering, wrote in to explain what happened:

Not how we wanted today to go. At approximately 9:00am PDT, we discovered that Twitter was inaccessible for all web users, and mobile clients were not showing new Tweets. We immediately began to investigate the issue and found that there was a cascading bug in one of our infrastructure components. This wasn’t due to a hack or our new office or Euro 2012 or GIF avatars, as some have speculated today. A “cascading bug” is a bug with an effect that isn’t confined to a particular software element, but rather its effect “cascades” into other elements as well. One of the characteristics of such a bug is that it can have a significant impact on all users, worldwide, which was the case today. As soon as we discovered it, we took corrective actions, which included rolling back to a previous stable version of Twitter.

According to the post recovery started at 1:00pm ET but that the whale awoke again at around 1:40pm ET; only to begin a full recovery near 2:08pm ET. After that, Twitter users noticed a slow restoration to what they usually get out of the service.

Twitter has managed to avoid the outage charts of late—unlike the fun we had with them during 2010—and they probably feel a little bit embarrassed about the event today. Acknowledging this, Rawashdeh wrote extensively about how well Twitter’s been doing for the past six months and hopes that they can keep that level of service up for the next six.

Meanwhile, we’ll keep an eye out for Twitter’s investigation about the origin of the “cascading bug” and for the moment at least the fail whale has gone back to bed.