resolutionMode

Controls how a domain-name resourceTarget is resolved. This applies only when the target is a domain name; it has no effect for IP-address targets, which have no name to resolve. In all cases the resolved address must be reachable from inside your VPC. Valid values:

• IN_VPC (default, recommended) – The target domain name is resolved privately, using the DNS resolvers of the VPC, such as private Route 53 hosted zones or on-premises DNS reachable from the VPC. Use this for targets that are private to your VPC, such as internal load balancers, private hosted-zone names, or on-premises hosts.

• PUBLIC – The target domain name is resolved against public DNS resolvers. Select this only when the target's domain name must be resolved through public DNS and the resulting address is still reachable from the VPC, an uncommon split-horizon configuration. If you are unsure, use IN_VPC.