How do I troubleshoot CNAME record errors in Route 53?

Resolution

The following errors might occur when you create a CNAME record in Route 53:

CNAME at the apex domain

Error message: "InvalidChangeBatch 400: RRSet of type CNAME with DNS name example.com. is not permitted at apex in zone example.com"

This error occurs because you can't create a CNAME record for your domain's zone apex (top node). For example:

• If your domain is example.com, then you can't create a CNAME record for example.com.
• You can create CNAME records for www.example.com or newproduct.example.com.

Solution: Create an alias record for your apex domain to point to your AWS resources such as:

• Amazon CloudFront distributions
• Load balancers
• Other records in the same hosted zone

Note: Alias records at the zone apex can't route traffic to a CNAME record.

For more information, see How do I create alias records in Route 53 for AWS hosted services?

DNS record conflicts

Error message: "InvalidChangeBatch 400: RRSet of type CNAME with DNS name test.example.com is not permitted as it conflicts with other records with the same DNS name in zone"

This error occurs when:

• A CNAME record conflicts with existing records.
• You can't have both a CNAME and an MX, A, or TXT record for the same subdomain.

Solution:

• Delete the conflicting DNS record if it's not in use
• Create an A-alias record that points the subdomain to your resource

For more information, see Deleting records.

Domain name label is too long

Error message: "Bad request. (InvalidChangeBatch 400: DomainLabelTooLong (Domain label is too long) encountered with 'org/services-and-resources/resources/classes-events/trauma-nurse'', Unparseable CNAME encountered)"

This error occurs when domain labels exceed the allowed length. Requirements:

• Each label must be 63 characters or fewer.
• The total domain name length, including the dots, can't exceed 255 characters.

Solution: Confirm that your domain names consist of a series of labels separated by dots. Each label can be up to 63 characters long. The total length of a domain name, including the dots, can't exceed 255 characters. Route 53 supports any valid domain name.

For more information, see DNS domain name format

Multiple values in a CNAME record

Error message: "Can't create a CNAME record that has different values for the same CNAME record"

This error occurs because a CNAME record:

• Must point to a single domain name.
• Can't point to multiple domain names or IP addresses.
• Must point to another domain, not an IP address.

Solution: To avoid this error, make sure that your CNAME record points to only one domain name and not to an IP address.

For more information, see CNAME record type.

Related information

Choosing between alias and non-alias records

Routing internet traffic to your AWS resources