A CNAME record is a record that maps a domain name (can be a subdomain), to a canonical domain name (can be a root domain or another subdomain). However, using CNAME has many considerations. Below enumerates the critical considerations when creating CNAME records.
- The domain name of a CNAME record must have no other records of other types (MX, TXT, etc.) that bear the same name (except for DNSSEC records like RRSIG and NSEC).
- A CNAME record pointing to another CNAME record is discouraged because it may lead to a loop and is inefficient.
- Some DNS providers don’t support Apex CNAME or CNAME placed at the root domain level.
- It is not a good practice for MX and NS records to point to a CNAME record.
- Domains that are used for email may not have a CNAME record, because this can have undesirable results with different mail servers.
VNIS supports Apex CNAME.