Service to Amazon, Wal-Mart and several other shopping sites was briefly blocked on Wednesday evening when their DNS provider was hit by a distributed denial of service (DDoS) attack.
Neustar, which provides DNS services to high profile website addresses under the UltraDNS brand, said the flood of malicious traffic, just two days before Christmas, was directed at the company's facilities in San Jose and Palo Alto, and that the effects were mostly limited to California users.
The websites were only down for about an hour — but needless to say at a very inopportune time for some. Neustar said that it first detected the trouble around 4:45 p.m. Pacific Time (12:45 AM Thursday, GMT).
Folks attempting last-minute shopping at Amazon, Wal-Mart, the Gap, and the travel site Expedia were ankled by outages and slow web browsing as a result of the DDoS attack. Other websites impacted include Salesforce.com and Linden Labs (maker of the game Second Life). In a message posted on Twitter, Jeff Barr of Amazon Web Services wrote that the retailer's outages were mostly in the US West Coast, and took down S3 and EC2 — as well as Amazon.com in "many places."
"We analyzed the patterns and were able to put mitigation measures in place within minutes of identifying the attack," NeuStar said in an emailed statement. "We had everything under control in well under an hour. The attack was limited to Northern California internet users. All along the way we were proactively communicating to our customers to let them know exactly what was happening and the steps we were taking."
This isn't the first time UltraDNS and its clients have been downed by DDoS attacks. In April, a larger DDoS attack took Amazon, SalesForce, Oracle and Juniper offline for several hours. Although more limited, Wednesday's malicious torrent of web traffic will insure that someone gets coal in their stocking. ®
This article is taken from http://www.theregister.co.uk/2009/12/24/ddos_attack_ultradns_december_09/