Azure Front Door: CNAME/alias record is not currently detected

When configuring a custom domain with Azure Front Door, one common issue that users may encounter is the “CNAME/alias record is not currently detected” message. This can be a confusing and frustrating experience, especially when you’re sure you’ve followed all the steps correctly. In this article, we’ll explore why this issue occurs and provide a step-by-step guide to resolve it.

Understanding the Issue

Azure Front Door is a scalable and secure entry point for fast delivery of your global applications. It allows you to define, manage, and monitor the global routing for your web traffic by optimizing for best performance and instant global failover for high availability.

When you add a custom domain to your Azure Front Door configuration, you’re required to create a CNAME record with your DNS provider that points to your Azure Front Door endpoint.. However, sometimes after setting up the CNAME record, you might find that Azure Front Door does not detect it, which is indicated by the “CNAME/alias record is not currently detected” status.

CNAME/alias record is not currently detected

Why does this happen?

There are several reasons why Azure Front Door might not detect your CNAME record:

• Propagation Delay – DNS records can take some time to propagate across the internet. Azure Front Door checks for the CNAME record’s presence, and if the propagation hasn’t completed, it won’t detect the record.
• Incorrect DNS Configuration – If the CNAME record is not correctly configured, Azure Front Door will not be able to detect it. This could be due to a typo in the record name or value, or incorrect TTL settings.
• Apex Domain Limitations – If you’re trying to configure an apex domain (also known as a root or naked domain), you cannot use a CNAME record due to DNS protocol limitations. Instead, you need to use an alias record if your DNS provider supports it.
• Certificate Propagation – If HTTPS is enabled, the certificate provisioning and propagation may take a few minutes because propagation is being done to all edge locations. During this time, the CNAME record might not be detected.

Step-by-Step Solution

Here’s how you can solve the “CNAME/alias record is not currently detected” issue:

Step 1: Verify the CNAME Record

1. Double-check the CNAME record you created with your DNS provider. Ensure that there are no typos and that the record points to the correct Azure Front Door endpoint.
2. If you’re using Azure DNS, you can create the CNAME records by selecting the “Add” button on the DNS management page.
3. For apex domains, ensure you’ve created an alias record instead of a CNAME record.

If you’re configuring an apex domain, Azure Front Door recommends using Azure DNS for hosting your apex domains because it supports alias records at the zone apex.

Step 2: Wait for Propagation

After verifying the CNAME record, wait for some time to allow for DNS propagation. This could take anywhere from a few minutes to 48 hours.

Step 3: Check for HTTPS Configuration

If you have enabled HTTPS on your custom domain, check the certificate provisioning status. Certificate propagation may take a few minutes.

Step 4: Validate Domain Ownership

For domain validation, create a DNS TXT record as instructed by Azure Front Door. This is necessary for both CNAME and alias records.

Step 5: Double Check Configuration andContact Support if Necessary

If you’ve followed all the steps and the issue persists, double check everything, then consider reaching out to Azure support for further assistance.

Conclusion

The “CNAME/alias record is not currently detected” issue in Azure Front Door can usually be resolved by ensuring correct DNS configuration, allowing time for propagation, and verifying HTTPS settings. Remember to use alias records for apex domains and validate domain ownership with a TXT record. With these steps, you should be able to successfully configure your custom domain with Azure Front Door and enjoy the benefits of a fast and reliable global web application delivery system.

Original Article Source: Azure Front Door: CNAME/alias record is not currently detected written by Chris Pietschmann (If you're reading this somewhere other than Build5Nines.com, it was republished without permission.)