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Tackling the AWS CloudFront ‘CNAMEAlreadyExists’ Error

Embarking on a website deployment journey with AWS is generally seamless, yet you might occasionally encounter specific roadblocks. A prevalent one is the CNAMEAlreadyExists error during the creation of a CloudFront distribution. This article aims to demystify this error and provide a detailed walkthrough to effectively address it.

Deciphering the ‘CNAMEAlreadyExists’ Error

The CNAMEAlreadyExists error emerges when attempting to inaugurate a new CloudFront distribution with a domain name (alias) that’s already in use by another distribution. Imagine the confusion of assigning identical phone numbers to two separate phones — the network would be at a loss directing calls!

Here’s a typical manifestation of this error:

Error: error creating CloudFront Distribution: CNAMEAlreadyExists: One or more aliases specified for the distribution includes an incorrectly configured DNS record that points to another CloudFront distribution.

Rectifying the CNAMEAlreadyExists error entails a series of investigative and corrective measures:

  1. Examine Current CloudFront Distributions: Initially, scrutinize any existing CloudFront distributions for domain names (aliases) identical to your desired one. Utilize the AWS Management Console or the AWS CLI to list your distributions:

    1

    aws cloudfront list-distributions

  2. Pinpoint and Rectify the Conflict: Upon discovering that the domain name is linked with another distribution, you must choose an appropriate course of action:

    • Revise the existing distribution if it’s meant to host your content.
    • Eliminate the conflicting alias from the existing distribution if it’s erroneously listed.

  3. Verify DNS Configuration: Confirm that your DNS records are accurately directing to the intended CloudFront distribution. Erroneous DNS configurations can trigger this error. In my case, utilizing Google Domains as a domain provider, the issue was rooted in a Custom Record entry that became obsolete (e.g., www.my.page Type: CNAME DATA:my-old-aws-distribution.cloudfront.net.) After removing this stale record and generating a new distribution in CloudFront, functionality was restored.

Wrapping it up 👏

Encountering the CNAMEAlreadyExists error might initially seem daunting, but a thorough understanding of its origins and a systematic approach to resolution can significantly streamline your AWS deployment process. Remember, diligent scrutiny of your configurations and a profound grasp of your resource interconnections are pivotal for an uninterrupted AWS journey.

Cheers! 🍺