Hello @Chris Schauer
Using a CNAME records in DNS presumes that you are pointing to a Fully Qualified Domain Name, as it is a record used to point to Canonical Names only.
In your typical case, you are trying to point a CNAME to your domain ’@’ which can only point an IP. As far as I know that kind of records, I would not use that kind of CNAME in my DNS zone file.
You can solve this issue in 2 ways :
You could point the ‘www’ subdomain to the PTR record of your IP address, and match the FQDN requirements to use a CNAME in your record.
You could use a second A record to point your 'www’ subdomain to the same IP as your domain. This solution is less elegant as it will need you update your DNS zone file twice each time an IP changes in your design.
Hope this helps with your query,
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