Last weekend, one of Amazon's cloud data centers shut down for several hours, due to a massive thunderstorm that made its way through the northern Virginia and Washington, DC areas. As a result, a number of popular online services that used Amazon's services, including Netflix, were affected by the outage.
Amazon has already offered up its explanation on what happened to its servers during that time. Now Netflix has done the same with a new post on its tech blog. Netflix said that the shut down of its streaming movie and TV service lasted about three hours and was "one of the most significant outages in over a year."
In examining what happened to Netflix's servers during that period, it found some issues with its load-balancing architecture. The blog said:
This caused unhealthy instances to fail to deregister from the load-balancer which black-holed a large amount of traffic into the unavailable zone. In addition, the network calls to the instances in the unavailable zone were hanging, rather than returning no route to host.
Netflix said it was working with Amazon to keep these kinds of problems from happening again. It also reiterated its faith in a cloud-based server system, saying:
We take our availability very seriously and strive to provide an uninterrupted service to all our members. We're still bullish on the cloud and continue to work hard to insulate our members from service disruptions in our infrastructure.
Netflix CEO Reed Hastings announced earlier this week that its users had streamed over 1 billion hours of video in June.