Amazon never provides much detail about its data center operations, and it's staying true to form with its recent performance issues, which began with a two-hour outage Friday and continued yesterday with intermittent downtime. John McNamara at Network World was tracking yesterday's rolling outages, which was later confirmed by monitoring at Keynote Systems, which said it was able to reach the main Amazon.com site as little as 30 percent of the time. Pingdom's monitoring system recorded seven minutes of total downtime. Amazon spokeswoman Patty Smith described Monday's troubles as "intermittent" and said they did not affect Amazon Web Services.
As for Friday's outage, Amazon said that its operations "are very complex and on rare occasions, despite our best efforts, they may experience problems." That vague statement has prompted others to fill in the blanks, including a detailed technical analysis from GigaOm and the inevitable rumors of a DDoS attack. UPDATE: A researcher at Narus says he detected a possible DDoS on IMDB.com (the Internet Movie Database), which is owned and hosted by Amazon, at the same time as the outages for Amazon.com. Narus says it didn't detect any direct attack on Amazon.com servers, and that the DDoS on IMDB totalled about 3 Mbits/sec.
There was also an interesting speculation from the gaming community. On Friday Amazon began a sale of a limited amount of highly-prized bundles of a PlayStation 3 80GB unit with Metal Gear Solid 4 (which doesn't officially launch until June 12). The bundle went on sale at 10 a.m. PST on Amazon, which noted prior to the sale that "demand for this item is so great, we anticipate selling out very quickly." By 10:25 a.m. the Amazon site was offline, and stayed down for two hours.
Here's the wrinkle: the gaming site Destructoid reports that the Playstation/Metal Gear 4 sale may have been the target of bot activity:
Rumor has it that the downtime is actually attributable to several bots set up prior to pre-order availability with the sole purpose of pre-ordering every bundle they possibly could, presumably to resell the bundles at inflated prices on eBay.
It wouldn't be the first time that bots have been used to try and lock in gaming products. Back in 2000, several retailers reported that their sites were being bombarded with traffic from bots seeking out scarce PlayStation 2 systems.
As has been noted elsewhere, Amazon has plenty of experience with denial of service attacks, and it would seem unlikely that demand for a single product could hobble its industrial-strength infrastructure. But it seems clear that something unusual or unexpected happened Friday. Given Amazon's status as the Web's most successful retailer - and the associated cost of downtime - its site performance will continue to be of interest to its customers, partners and the data center community.