By Jordan Valinsky, CNN
New York (CNN) — Amazon Web Services (AWS), the cloud computing platform that powers much of the Internet, was offline for several hours on Monday, causing several major problems. websites and apps don’t work.
From banking services to social networking, airline booking sites and online shopping, thousands of services were disrupted as millions of people around the world – many of whom were commuting to work on the US East Coast – were unable to order coffee or access key apps on their mobile.
The latest outage is a reminder of how vulnerable the backbone of the internet can be, even if the disruption is short-lived, and how dependent the world has become on these online services.
While AWS and its competitors are generally robust, the Internet is a complex web of overlapping services that are only as reliable as their weakest code. The cause of Monday’s outage remains unknown, but a service that converts friendly web names into IP addresses was unable to communicate with the massive databases of thousands of companies hosted by Amazon.
Previous outages on this scale have been caused by a wide range of errors, including faulty updates, the accidental injection of bad code, or a change to third-party software that does not interact properly with a service. In rare cases, internet cable breaks, cyberattacks, or direct denial-of-service attacks can cripple or overload servers hosting important apps.
But the relative frequency of these events demonstrates the lack of necessary layoffs and competitive services. Some internet experts say that companies too often put all their eggs in one basket of cloud services.
There are “no signs” this was a cyberattack, said Rob Jardin, chief digital officer at cybersecurity firm NymVPN, adding that it “appears to be a technical glitch affecting one of Amazon’s key data centers.”
“The internet was originally designed to be decentralized and resilient, but today much of our online ecosystem is concentrated in a small number of cloud regions,” he said in a note. “When one of those regions experiences an outage, the impact is immediate and widespread.”
Jardin said: “These issues can occur when systems become overloaded or a key part of the network goes down; and because so many websites and apps rely on AWS, the impact spreads quickly.”
It’s not often that AWS experiences such major disruptions, with the latest happening in 2021.
“That’s on par with the other major cloud providers, and it’s even amazing that they can run at the scale they are now without more frequent disruptions,” said Mike Chapple, a cybersecurity expert and IT professor at the University of Notre Dame’s Mendoza College of Business.
“The reason these events attract a lot more attention is because of their impact,” he told CNN. “If a single company experiences a problem in its data center, it causes problems for that company’s products and services.”
In 2024, the largest IT outage ever brought down large parts of the internet when a devastating CrowdStrike software bug crashed computers, led to flight cancellations and disrupted hospitals around the world, causing $5 billion in direct business losses. A bug in CrowdStrike’s cloud-based testing system caused a problematic update to computers around the world.
Also last year, AT&T’s network went down several times, including an 11-hour meltdown that left many gig workers unable to do their jobs.
What went wrong on Monday?
AWS is a cloud computing provider that hosts many of the world’s most used online services. In Amazon’s infancy, the company needed excess server capacity to ensure it had enough computing power to handle the massive amounts of traffic coming to its site during the holidays. Amazon realized it could use those servers for the rest of the year to support other companies’ online needs, and out of that was born AWS.
One of AWS’s many offerings is DynamoDB, a database that hosts information for businesses, including customer data. Amazon said on Monday that its customers could not access data stored in DynamoDB because its Domain Name System (DNS) – a kind of phone book for the Internet – had encountered a problem.
DNS is like an Internet location engine, turning user-friendly web addresses like amazon.com into IP addresses – a series of numbers that other websites and applications can understand.
“Amazon had the data safely stored, but no one else could find it for hours, leaving apps temporarily separated from their data,” Chapple said. “It’s as if large parts of the internet are suffering from temporary amnesia.”
It’s not clear what caused the DNS outage, but it only lasted a few hours. By 6:35 a.m. ET, Amazon had resolved the DNS issue and recommended that companies dump their cache (temporary storage files) to help speed up the recovery of their services.
Amazon said the outage continued to affect other AWS services, including EC2 – a type of virtual server that many companies use to build their online applications.
The company will likely conduct an autopsy in the coming days and explain what went wrong with its DNS system.
The CNN Wire
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