AWS Certified Advanced Networking – Specialty (ANS-C01)Network DesignHard
A large manufacturing company has a hybrid cloud environment, with critical applications running both on-premises and in AWS. They need to ensure that their on-premises users can consistently resolve DNS records for AWS resources, including private hosted zones, and that AWS applications can resolve on-premises DNS records. The solution must be fault-tolerant and highly available. Which AWS service provides the most robust solution for this bidirectional DNS resolution?
- AEstablishing a VPN connection and manually configuring `/etc/hosts` files.
- BDeploying a DNS forwarder on an EC2 instance in each VPC.
- CUtilizing Amazon Route 53 Resolver Endpoints (Inbound and Outbound).
- DConfiguring public DNS records in Route 53 for all AWS resources.
Show answer & explanationAnswer & explanation
Correct answer: C. Utilizing Amazon Route 53 Resolver Endpoints (Inbound and Outbound).
Amazon Route 53 Resolver Endpoints (Inbound and Outbound) are explicitly designed for highly available and fault-tolerant bidirectional DNS resolution between on-premises networks and AWS VPCs. Inbound endpoints handle queries from on-premises to AWS private zones, while Outbound endpoints forward queries from AWS to on-premises DNS servers.
Why the other options are wrong
- A. Manually configuring `/etc/hosts` files is unscalable, error-prone, and provides no fault tolerance or dynamic updates.
- B. Deploying custom DNS forwarders on EC2 instances is not fault-tolerant, requires significant management overhead, and is not a managed AWS service for hybrid DNS.
- D. Using public DNS records for internal AWS resources is a security risk and doesn't address resolving on-premises records from AWS.
Route 53 Resolver Endpoints (Hybrid DNS)
AWS Route 53 Resolver Endpoints enable secure, highly available, and scalable bidirectional DNS resolution between on-premises DNS servers and Amazon VPCs.
- Inbound endpoints for on-premises to AWS resolution
- Outbound endpoints for AWS to on-premises resolution
- Managed service, highly available and fault-tolerant
- Eliminates need for custom DNS infrastructure
Memory trick: Resolver Endpoints bridge your DNS worlds securely.