What solution would create the LEAST complex DNS architecture and ensure that each VPC can resolve all AWS resources?
Create a shared services VPC in a central account, and create a VPC peering connection from the shared services VPC to each of the VPCs in the other accounts. Within Amazon Route 53, create a privately hosted zone in the shared services VPC and resource record sets for the domain and subdomains. Programmatically associate other VPCs with the hosted zone.
Create a VPC peering connection among the VPCs in all accounts. Set the VPC attributes enableDnsHostnames and enableDnsSupport to ג€trueג€ for each VPC. Create an Amazon Route 53 private zone for each VPC. Create resource record sets for the domain and subdomains. Programmatically associate the hosted zones in each VPC with the other VPCs.
Create a shared services VPC in a central account. Create a VPC peering connection from the VPCs in other accounts to the shared services VPC. Create an Amazon Route 53 privately hosted zone in the shared services VPC with resource record sets for the domain and subdomains. Allow UDP and TCP port 53 over the VPC peering connections.
Set the VPC attributes enableDnsHostnames and enableDnsSupport to ג€falseג€ in every VPC. Create an AWS Direct Connect connection with a private virtual interface. Allow UDP and TCP port 53 over the virtual interface. Use the on-premises DNS servers to resolve the IP addresses in each VPC on AWS.
Explanations:
This option creates a centralized private DNS solution using a shared services VPC and VPC peering. It minimizes complexity by having one centrally managed Route 53 private hosted zone, making it easier to manage DNS records for all resources across accounts. The programmatic association of VPCs ensures that all VPCs can resolve DNS names without duplicating hosted zones in each account.
This option requires establishing VPC peering among all VPCs, which can become complex as the number of accounts increases. Each VPC must manage its own Route 53 private hosted zone, leading to potential inconsistencies and additional management overhead. This architecture is less efficient compared to a centralized approach.
While this option is similar to A, it does not explicitly mention the programmatic association of the hosted zone with each VPC. Additionally, allowing UDP and TCP port 53 over VPC peering connections can introduce complexity in security group and route management. Without clear management practices, it may lead to difficulties in scaling and maintaining DNS records.
This option disables DNS support within each VPC and relies on on-premises DNS servers. It introduces unnecessary complexity by requiring a Direct Connect connection and managing DNS resolution externally, which goes against the goal of simplifying DNS architecture within AWS accounts. Additionally, it does not facilitate seamless resolution of AWS resources across accounts.
I scheme that the answer is:
Create a shared services VPC in a central account, and create a VPC peering connection from the shared services VPC to each of the VPCs in the other accounts. Within Amazon Route 53, create a privately hosted zone in the shared services VPC and resource record sets for the domain and subdomains. Programmatically associate other VPCs with the hosted zone.