The global outage of cloud computing services provider Fastly was caused by an undiscovered software bug, the company has admitted.
The bug, which was introduced to the company's system last month, surfaced on Tuesday "when it was triggered by a valid customer configuration change", according to Fastly's Engineering and Infrastructure SVP Nick Rockwell.
The hour-long "global CDN disruption", which took place on 8 June, affected the online services of numerous governmental portals, news outlets, and IT and code-hosting websites such as GitHub and Stack Overflow. Amazon and he UK government's online portal were also among countless other websites taken offline.
In a statement on the company's website, Rockwell said that "a customer pushed a valid configuration change that included the specific circumstances that triggered the bug", causing 85% of Fastly's network to "return errors".
"We detected the disruption within one minute, then identified and isolated the cause, and disabled the configuration. Within 49 minutes, 95% of our network was operating as normal. This outage was broad and severe, and we're truly sorry for the impact to our customers and everyone who relies on them," he added.
Rockwell added that the company has taken appropriate measures to prevent future issues, including deploying the bug fix across Fastly's network as well as conducting a complete post mortem of the processes and practices that were followed during the incident.
The secure cloud configuration imperative
The central role of cloud security posture management
The company will also determine why the bug hadn't been detected during quality assurance and testing processes and will evaluate ways to improve its remediation time.
However, Fastly didn't provide further details on the nature of the bug. IT Pro has reached out to the company and will update this article when more information becomes available.
Commenting on the events, Angelique Medina, director of Product Marketing at network intelligence company Cisco ThousandEyes, said that the outage is an example of how interconnected the web is.
"Most of the sites we visit, the apps we use and the media we consume are delivered by Content Delivery Network (CDN) providers. By caching web content close to users for maximum performance and availability, they're critical to how we access digital services," she told IT Pro.
"Together with major public cloud providers who host or provide services to the most-used sites and applications online, the delivery mechanism that is the Internet is largely powered by a few providers and whenever something goes wrong with one of them, it can have a massive impact on web users globally."
