Amazon Web Services is investigating problems with CloudFront, its content delivery network.
The cloud computing service is investigating issues across North America, South America, Europe and Asia Pacific.
The AWS status page shows CloudFront as still functioning. However, a message timestamped 5pm PST (12pm AEST) stated: "We are currently investigating increased error rates for DNS queries for CloudFront distributions."
Update: AWS now lists the issue as resolved. A message timestamped 6.24pm PST states: Between 4:12 PM and 6:02 PM PST, users experienced elevated error rates when making DNS queries for CloudFront distributions. The service has recovered and is operating normally.
"We haven’t received a post-mortem from Amazon but the CloudFront outage appears to have been a network-wide issue for Amazon, caused by a fault in its DNS service," said Stewart McGrath, the CEO of Web acceleration specialist Squixa, which provides a multi-CDN platform.
"Though the problem has since been rectified, it has come at a bad time for online retailers preparing for Black Friday and Cyber Monday in the United States — it's like having your store closed because someone forgot the key to the front door."
"For websites and retailers that are heavily reliant on CloudFront, it would mean they needed to direct all traffic and Web requests back to their origin Web server. If their origin server was not built for that sort of traffic load, they would suddenly see a significant impact on performance."
McGrath said businesses should consider using multiple CDNs or a third-party platform of the type Squixa offers, which can switch between CDNs, to reduce the risk of outages.
Earlier this month Microsoft's Azure cloud suffered a service interruption.
Microsoft later revealed the root cause was an update to Azure Storage gone awry.
"During the rollout [of a performance update to Azure Storage] we discovered an issue that resulted in storage blob front ends going into an infinite loop, which had gone undetected during flighting," Jason Zander from the company's Azure team wrote in a blog entry.
"The net result was an inability for the front ends to take on further traffic, which in turn caused other services built on top to experience issues."