Millions of blogs hosted by LiveJournal and TypePad were unavailable throughout Tuesday night and into Wednesday morning as a massive denial-of-service attack struck their servers.
The attack that brought down the servers at Six Apart -- the San Francisco company behind the LiveJournal and TypePad services, and the Moveable Type blogging software -- began at 4 p.m. PDT Tuesday, according to an advisory posted to the firm's Web site by Michael Sippey, the vice president of product.
"Six Apart has been the victim of a sophisticated distributed denial of service attack," said Sippey. "This has affected all of Six Apart's sites, causing intermittent and limited availability for TypePad, LiveJournal, TypeKey, sixapart.com, movabletype.org and movabletype.com."
By 11:40 p.m. Tuesday, service had been partially restored, and 3:50 a.m. Wednesday, access was back to normal.
"Our operations staff continues to work with our access providers to monitor the situation," added Sippey.
In a denial-of-service (DoS) attack, hackers overwhelm servers by flinging unusually high levels of Net traffic at their IP addresses. The result is slow servers at best, crashed servers at worst. Last December, Six Apart suffered from a 12-hour outage that the company said was due to a glitch in routine server maintenance. In the months before that, TypePad users in particular became irate over poor performance, and threatened to take their blogs elsewhere.
In December, Six Apart let customers pick the compensation for the outage, which included everything from no credit to a 45-day usage credit.
This time, however, Six Apart has no plans for something similar. "We take great pride in the reliability and stability of our operation," said Jane Anderson, spokesperson for Six Apart, late Wednesday. Our uptime has been 99.99 percent for a long time, but clearly this wasn't an outage or caused by something we did."
In fact, the attack wasn't directed against Six Apart specifically, but against what Anderson described as "a security company. It was brought down and we ended up on the receiving end."
Six Apart has been hit by DoS attacks before, but this, said Anderson, was the largest ever. The company has reported the incident to the FBI, and will work with law enforcement in any attempt to locate and charge the attackers.