Examkin

Question

Difficulty: Very hardHigh Availability and Disaster Recovery Design

A global digital publishing platform is designing a highly available, multi-region architecture to host its core subscription system on AWS. The primary environment is deployed in the us-east-1 Region, and the secondary disaster recovery (DR) environment is in the us-west-2 Region. The business requires a Recovery Time Objective (RTO) of 15 minutes and a Recovery Point Objective (RPO) of 1 minute, while minimizing active compute costs and management overhead. The database layer utilizes Amazon Aurora PostgreSQL. The application must support outbound connections to external validation services that remain resilient during Availability Zone (AZ) outages in either Region. Furthermore, internal containerized microservices in both Regions must resolve private DNS names across the peered VPCs. Which combination of actions should the Solutions Architect take to meet these requirements? (Select TWO.)

  1. Configure an Amazon Aurora Global Database with the primary cluster in us-east-1 and a secondary cluster in us-west-2. Associate the Route 53 Private Hosted Zones containing internal microservice endpoints with the VPCs in both Regions.Answer
  2. Deploy a NAT Gateway in each Availability Zone within the public subnets of both Regions, and configure the route tables of the private subnets to route outbound traffic through the local NAT Gateway in their respective Availability Zone.Answer
  3. C
    Configure a daily snapshot backup policy for Amazon RDS for PostgreSQL in us-east-1, copy the snapshots to us-west-2 using AWS Backup, and restore the database from the snapshot in us-west-2 during failover to minimize active database costs.
  4. D
    Configure Route 53 Private Hosted Zones in us-east-1 and rely on a shared Transit Gateway to automatically route and resolve DNS queries from the us-west-2 VPC without explicitly associating the host zone with the secondary VPC.
  5. E
    Deploy a single NAT Gateway in one public subnet per Region to minimize NAT Gateway hourly costs, and update the route tables of all private subnets across all Availability Zones in that Region to use this single NAT Gateway.
  6. F
    Enable Amazon Aurora Replica Auto Scaling on the reader nodes within the us-west-2 secondary cluster to dynamically scale and automatically accept write operations during a primary Region degradation.

Answer

Configuring Amazon Aurora Global Database for sub-second database replication and associating Route 53 Private Hosted Zones with all peer VPCs, combined with deploying a NAT Gateway in each Availability Zone in both Regions to ensure highly available outbound connections.
The configuration containing Amazon Aurora Global Database handles database tier high availability and meets the 1-minute RPO because replication lag is measured in sub-seconds. Associating the Route 53 Private Hosted Zones directly with all VPCs in both Regions resolves cross-region private DNS query needs. Deploying a separate NAT Gateway in each public subnet per Availability Zone guarantees that a single zone outage does not compromise internet-bound traffic from private resources residing in other zones.

Step-by-Step Solution

1
Analyze the database RTO and RPO requirements to choose the correct storage replication tier.
An Amazon Aurora Global Database is chosen because it replicates database updates to the secondary Region with a lag of less than 1 second, fulfilling the 1-minute RPO, whereas snapshot-based approaches fail this constraint.
To ensure replication lag remains within the required bounds during peak write loads.
2
Establish private DNS resolution across peered VPCs in different AWS Regions.
The Route 53 Private Hosted Zones containing internal microservice endpoints are associated with both the primary and secondary VPCs.
To allow internal container instances in both VPCs to resolve cross-region private endpoints without routing queries over public DNS resolvers.
3
Design outbound internet connectivity for private subnets that survives Availability Zone failures.
A NAT Gateway is deployed in each Availability Zone's public subnet, and route tables for private subnets are updated to target their zone-specific NAT Gateway.
Deploying a single NAT Gateway creates a single point of failure, whereas zone-specific NAT Gateways ensure high availability for outbound traffic.

Key Concept

Multi-region high availability and disaster recovery planning, combining Aurora Global Database replication, cross-VPC private DNS resolution, and redundant zone-specific NAT gateways.
Estimated Time:3m 0s
Rate this question

Topics

High Availability and Disaster Recovery Design

More questions from this topic