Microsoft Web Sites Knocked Offline by Technical Error
Many of the most popular Internet sites operated by Microsoft Corp. were knocked offline for much of the day Wednesday in a costly series of outages triggered by the company’s own technical blunder.
The intermittent outages affected Microsoft.com, the company’s main site, Internet Web portal MSN.com, the Expedia.com travel service, the Hotmail e-mail service and a handful of other sites that attract millions of visitors, and transact millions of dollars in business, every day.
The outages were the latest reminder of the reliability problems that continue to plague high-traffic Web sites. Glitches at auction house EBay earlier this month prevented users from placing bids on items for much of a day.
After speculation during the day that Microsoft had been the victim of a computer hacker, the company said that the problem had been traced to a single adjustment made to a key link in its network by a company technician at 6:30 p.m. Tuesday.
After finally diagnosing the problem late Wednesday, the company “removed the changes and saw massive improvement,” said Adam Cohn, a Microsoft spokesman. It was, he said, “an operational error, not a problem with our products or the security of our network.”
The glitch affected routers that direct Internet traffic to Microsoft’s Web servers, Cohn said. The company’s Web site servers were fully operational, but the troubled router wouldn’t let users through.
“Imagine a line to get in a doorway,” Cohn said. “Inside, the house is fine. But the line is so packed that people can’t get in.”
Experts said news of the outages may have contributed to Microsoft’s problems by creating a stampede to the company’s sites by curious Web surfers.
The problems impeded the flow of traffic to so-called domain name system servers that are invisible to everyday Internet users but are critical to the flow of Internet traffic. These DNS servers don’t host the actual content of a site, but translate the domain name--such as https://www.microsoft.com that users type into their computer--into the numeric IP address where the site’s data actually reside.
Microsoft has four DNS servers that route traffic to most of its Web sites, meaning a breakdown that prevents users from accessing just a few machines could render much of the company’s vast Internet real estate inaccessible.
Earlier Wednesday, experts wondered whether hackers had exploited that vulnerability, launching an attack slightly more clever than the denial-of-service assault on Yahoo, EBay and other popular sites last February.
Those attacks relied on brute force, as hackers bombarded Web sites with so many artificially generated requests for service that the sites buckled under the load.
Attacking a company’s DNS servers “would be smarter,” theorized John Vranesevich, founder of the security consulting firm AntiOnline. “Instead of having to send that huge amount of data to so many different networks, you can send it to a handful of machines and achieve the same effect.”
The Microsoft sites down Wednesday are among the Net’s most popular. MSN.com attracts more than 10 million visitors a day, according to Jupiter Media Metrix, and Microsoft.com attracts 2 million visitors a day.
Despite its software prowess, Microsoft has suffered a series of embarrassing online breakdowns in recent years. In October, the company acknowledged that hackers had been secretly breaking into the company’s corporate network.
