How Resolver determines whether the domain name in a query matches any rules
Route 53 Resolver compares the domain name in the DNS query with the domain name in the rules that are associated with the VPC that the query originated from. Resolver considers the domain names to match in the following cases:
The domain names match exactly
The domain name in the query is a subdomain of the domain name in the rule
For example, if the domain name in the rule is acme.example.com, Resolver considers the following domain names in a DNS query to be a match:
acme.example.com
zenith.acme.example.com
The following domain names are not a match:
example.com
nadir.example.com
If the domain name in a query matches the domain name in more than one rule (such as example.com and www.example.com), Resolver routes outbound DNS queries using the rule that contains the most specific domain name (www.example.com).