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AWS outage affects major websites and apps globally

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Issue originated in US site known for outages

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Service improved, then problems recurred before recovery

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Gaming and financial platforms among those impacted by AWS

issue

(Updates to reinstate, no change to text.)

By Greg Bensinger, Shubham Kalia and Deborah Mary Sophia

SAN FRANCISCO, Oct 20 (Reuters) - Amazon.com ( AMZN ) cloud

service returned to normal operations on Monday afternoon, the

company said, after an internet outage that caused global

turmoil among thousands of sites, including some of the web's

most popular apps like Snapchat and Reddit ( RDDT ).

Still, Amazon ( AMZN ) said some AWS services had a backlog

of messages that would take a few hours to process.

AWS hosts applications and computer processes for companies

around the world, and the disruption knocked workers from London

to Tokyo offline and halted others from conducting normal

everyday tasks like paying hairdressers or changing their

airline tickets. Users on Monday afternoon had complained of

lingering difficulties using services such as digital wallet

Venmo and video calling site Zoom.

It was the largest internet disruption since last year's

CrowdStrike ( CRWD ) malfunction hobbled technology systems in hospitals,

banks and airports, highlighting the vulnerability of the

world's interconnected technologies.

It was at least the third time in five years that AWS's

northern Virginia cluster, known as US-EAST-1, contributed to a

major internet meltdown.

Amazon ( AMZN ) did not address a request for more clarity about why

that particular data center keeps being impacted. The problems

stemmed from what is known as the Domain Name System, or DNS,

which prevented applications from finding the correct address

for AWS's DynamoDB API, a cloud database relied upon to store

user information and other critical data.

ROOT CAUSE IS NETWORK HEALTH MONITOR

Earlier, AWS said the root cause of the outage was an

underlying subsystem that monitors the health of its network

load balancers used to distribute traffic across several

servers.

The issue, AWS said, originated from within the "EC2

internal network", Amazon's ( AMZN ) "Elastic Compute Cloud" service,

which provides on-demand cloud capacity within AWS.

Shortly after 3 p.m. PT (2200 GMT), Amazon ( AMZN ) said, "all AWS

services returned to normal operations. Some services such as

AWS Config, Redshift, and Connect continue to have a backlog of

messages that they will finish processing over the next few

hours."

Ken Birman, a computer science professor at Cornell

University, said software developers need to build better fault

tolerance. He said AWS provides tools developers can use to

protect themselves in the event of a problem at one of any of

its sprawling network of data centers, and developers can also

create backups with other cloud providers.

"When people cut costs and cut corners to try to get an

application up, and then forget that they skipped that last step

and didn't really protect against an outage, those companies are

the ones who really ought to be scrutinized later," Birman told

Reuters.

ISSUE ORIGINATED FROM AWS SITE KNOWN FOR PREVIOUS OUTAGES

AWS provides computing power, data storage and other digital

services to companies, governments and individuals and is the

world's largest cloud provider, followed by Microsoft's ( MSFT )

Azure and Alphabet's Google Cloud.

Disruptions to its servers can cause outages across websites

and platforms - ranging from food delivery apps to gaming

platforms and airline systems - that rely on its cloud

infrastructure.

AWS said on its status page that Monday's outage originated

at its US-EAST-1 location, its oldest and largest for web

services. The site suffered outages in 2021 and 2020.

According to documentation on the AWS website, the US-EAST-1

site is often the default region for many AWS services.

"FRAGILE INFRASTRUCTURES"

The problem highlights how interconnected everyday digital

services have become and their reliance on a small number of

global cloud providers, with one glitch wreaking havoc on

business and day-to-day life, experts and academics said.

"This outage once again highlights the dependency we have on

relatively fragile infrastructures," said Jake Moore, global

cybersecurity advisor at European cybersecurity firm ESET.

In Britain, Lloyd Bank, Bank of Scotland and

telecom service providers Vodafone ( VOD ) and BT were

all hit, according to Downdetector's UK website, as was UK tax,

payments and customs authority HMRC's website.

"The main reason for this issue is that all these big

companies have relied on just one service," said Nishanth

Sastry, director of research at the University of Surrey's

Department of Computer Science.

Ookla, which owns Downdetector, said over 4 million users

reported issues due to the incident.

"For major businesses, hours of cloud downtime translate to

millions in lost productivity and revenue," said Ryan Griffin,

U.S. cyber practice leader at insurance broker McGill and

Partners.

Wall Street was largely unfazed, sending Amazon ( AMZN ) shares 1.6%

higher to $216.48.

FROM SNAPCHAT TO VENMO: OUTAGE TAKES DOWN APPS

Ookla said at least a thousand companies were affected by

the outage.

Apps like Reddit ( RDDT ), Roblox ( RBLX ), Snapchat

and Duolingo ( DUOL ) had all been affected.

Artificial intelligence startup Perplexity, cryptocurrency

exchange Coinbase and trading app Robinhood

all experienced platform disruptions and attributed them to AWS.

Amazon's ( AMZN ) own services, including its shopping website, Prime

Video and Alexa, were also hit.

Fortnite, owned by Epic Games, Clash Royale and Clash of

Clans were among the gaming platforms affected. Uber ( UBER )

rival Lyft ( LYFT ) was also knocked down in the United States.

In a post on X, Signal President Meredith Whittaker

confirmed the messaging app was hit by the outage, though

billionaire Elon Musk, who owns X, said his platform continued

to work.