Examkin

Question

Difficulty: MediumBackup and Restore Management

A company's production database runs on an Amazon RDS for PostgreSQL DB instance. A SysOps Administrator must establish a cross-Region disaster recovery (DR) solution that guarantees a Recovery Point Objective (RPO) of less than 30 minutes and a Recovery Time Objective (RTO) of less than 15 minutes. Which strategy should the administrator implement to meet these requirements?

  1. A
    Enable Multi-AZ deployment for the DB instance and specify the disaster recovery Region as the secondary Availability Zone to automate synchronous replication and failover.
  2. B
    Configure Amazon S3 Cross-Region Replication (CRR) to replicate the automated DB snapshots from the source Region's automated backup bucket to a destination bucket, without enabling S3 versioning on either bucket.
  3. Create a cross-Region Read Replica of the DB instance in the disaster recovery Region. During a disaster, promote the Read Replica to a standalone DB instance and update the application endpoint.Answer
  4. D
    Configure a Route 53 active-active failover routing policy between the primary DB instance and a cross-Region Read Replica without health checks, allowing Route 53 to automatically redirect write traffic during a regional outage.

Answer

Create a cross-Region Read Replica of the DB instance in the disaster recovery Region. During a disaster, promote the Read Replica to a standalone DB instance and update the application endpoint.
Creating a cross-Region Read Replica provides asynchronous replication to another AWS Region, which typically keeps replication lag (RPO) to under a few minutes. If a regional disaster occurs, promoting the Read Replica to a standalone DB instance and modifying the application's endpoint is a quick operation that easily fits within the 15-minute RTO.

Step-by-Step Solution

1
Analyze the cross-Region disaster recovery requirements (RPO of 30 minutes, RTO of 15 minutes).
Determine that the replication must cross AWS Regions, and the recovery process must take less than 15 minutes.
This establishes the constraints needed to evaluate the options.
2
Evaluate the capabilities of Amazon RDS Multi-AZ.
Determine that Multi-AZ replication is synchronous but only functions within a single AWS Region.
This rules out standard Multi-AZ for cross-Region DR.
3
Evaluate using Amazon S3 Cross-Region Replication (CRR) for automated backups.
Identify that RDS automated backups cannot be replicated using S3 CRR directly, and S3 CRR requires versioning on both buckets.
This rules out S3 CRR without versioning on system-managed buckets.
4
Evaluate the cross-Region Read Replica solution.
A cross-Region Read Replica provides asynchronous cross-Region replication (low RPO). Promoting the replica to a standalone instance takes minutes (low RTO).
This confirms that Read Replica promotion meets both the RPO and RTO requirements.

Key Concept

Cross-Region disaster recovery for Amazon RDS using Read Replicas.
Rate this question

Topics

Backup and Restore Management

More questions from this topic