Half of the internet was down on Monday. Here’s why

If you were among the many who were unable to log into Snapchat or Zoom on Monday, take solace in the fact that you weren’t alone. Huge parts of the internet went down yesterday with sites and services such as Snapchat, Fortnite, Venmo, the PlayStation Network and, Amazon all being unavailable for users.

And all of this happened because Amazon’s computing services unit, Amazon Web Services (AWS) was hit by a major global outage.

Now, 24 hours later, the cloud service has returned to normal operations but it does serve as a another reminder of how consumers, businesses and even government organisations rely on AWS and its massive cloud to make their websites, apps and other online services work.

So, what exactly happened? What caused the outage? Which sites and services were down?

What is Amazon Web Services?

For those wondering what exactly is AWS, here’s what it is.

Amazon Web Services provides cloud computing services to customers, including companies and organisations across various sectors. Cloud computing is a technology that allows companies to remotely access massive computing equipment and services without having to purchase and maintain physical infrastructure.

Businesses ranging from Snapchat to McDonald’s essentially rent Amazon’s physical infrastructure located in places all around the world to operate their own websites. Instead of building expensive computing systems in-house, companies rely on Amazon to store data, develop and test software and deliver applications.

As of today, AWS holds 30 per cent of the market share followed by Microsoft Azure (20 per cent) and Google Cloud (13 per cent), according to the Synergy Research Group. These three firms have been dubbed ‘The Big Three’.

So, what happened to AWS services on Monday?

On Monday, just after 3 am ET (around 12.30 pm IST), users across the world began to report widespread access issues for websites and apps across Downdetector and similar monitoring platforms. According to Downdector, they received more than 6.5 million reports Monday.

At 4:26 am ET, Amazon flagged the issue, stating: “We can confirm significant error rates for requests made to the DynamoDB endpoint in the US-EAST-1 Region.”

At 11:43 am, AWS provided an update on the root cause of the disruption, referring to it as “an underlying internal subsystem responsible for monitoring the health of our network load balancers.” Amazon stated it was “actively working on mitigations” to tackle the far-reaching issue.

For many, the disruptions continued for more than two hours, with some users, mostly in the US, seeing issues persist for over six hours. Finally, AWS announced that core issues had been resolved and most services were recovering, but intermittent disruptions persisted into the morning.

Which sites and services were affected?

From banking services to social networks to airline booking sites to online shopping, thousands of services were disrupted for millions of people worldwide.

Social media apps such as Snapchat, Facebook, and Reddit saw a sharp rise in reports of connectivity issues. At its peak, the Snapchat-related reports reached over 7,000 globally. Even gaming apps and websites experienced significant disruption. Fornite, Roblox, and Clash of Clans all experienced a spike in connectivity issue reports, with users unable to login to their accounts.

According to DownDetector, even Delta Air Lines and United Airlines experienced disruptions. People even complained of having difficulty accessing their Amazon products such as Alexa, the smart speaker, and Ring doorbell cameras.

Coinbase, a cryptocurrency exchange, posted on social media site X that some users couldn’t access the company’s online platform because of the AWS outage but that “all funds are safe.”

Zoom services also experienced technical issues owing to the outage. So did the dating app, Hinge.

In the UK, bank customers complained of being unable to log into their accounts. The UK government’s tax and customs service, HMRC, also encountered issues as the official UK government services website, Gov.uk, was impacted.“We are aware of an incident affecting Amazon Web Services, and several online services which rely on their infrastructure,” a UK government spokesperson told TIME via an email. “Through our established incident response arrangements, we are in contact with the company, who are working to restore services as quickly as possible.”

Graphic design tool Canva said it was “experiencing significantly increased error rates which are impacting functionality on Canva. There is a major issue with our underlying cloud provider.”

Other apps and websites that reported issues include: Venmo, Hulu, McDonald’s, Signal, Wordle, Slack, Canva, Tidal, PokemonGo, Strava, and WhatsApp.

As companies dealt with the aftermath of the outage, Elon Musk mocked AWS by posting “X works” on the social media site he owns.

But what caused this AWS outage?

As site after site and service after service reported issues, many speculated that a cyberattack was the cause of it. Rob Jardin, chief digital officer at cybersecurity company NymVPN, told CNBC and CNN that “there’s no sign that this AWS outage was caused by a cyberattack — it looks like a technical fault affecting one of Amazon’s main data centres.”

“These issues can happen 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,” he said in the statement.

Initially, AWS didn’t share what was the cause of the outage, but offered a brief explanation: “The root cause is an underlying internal subsystem responsible for monitoring the health of our network load balancers.”

Later on, AWS updated its service page, saying the outage started with an error with its Domain Name System (DNS) at Amazon’s northern Virginia data plant, located in what is known as the ‘Data Center Alley,’ where hundreds of data centres are located.

But what is a DNS? The DNS is like an internet location engine, converting user-friendly web addresses like amazon.com into IP addresses – a series of numbers that other websites and applications can understand. If the DNS is not working, a lookup takes too long and a website may timeout. For users, it could also seem like the website they’re looking for no longer exists or simply can’t be found.

Most tech experts note that it is common to experience issues with DNS, but owing to the reach of AWS, the scale of the outage on Monday was rare.

The company is likely to conduct a postmortem and explain what went wrong with its DNS system in the coming days.

How much did AWS outage cost?

Owing to the large reach of AWS, the outage certainly caused losses to services across the world. The question is how much.

Most experts note that it’s difficult to estimate the financial impact of the AWS outage. However, Tenscope has carried out an initial analysis, estimating that major websites lose $75 million every hour when they go down.

Mehdi Daoudi, CEO of internet performance monitoring firm Catchpoint, told Jazeera that the financial impact of the outage could “easily reach into the hundreds of billions” due to lost productivity and halted business operations.

Have AWS outages occurred before?

Yes. A disruption in 2023 knocked many websites offline for several hours.

However, AWS’s longest outage in recent history occurred in late 2021, when companies — everything from airline reservations and auto dealerships to payment apps and video streaming services — were affected for more than five hours.

Other major outages happened in 2020 and 2017. The 2017 incident, notably, occurred after an employee typed the wrong command during a debugging procedure, resulting in the shutdown of more servers than expected.

With inputs from agencies