Google Cloud Professional Cloud Database Engineer — Question 112

You are migrating an on-premises application to Google Cloud. The application requires a high availability (HA) PostgreSQL database to support business-critical functions. Your company's disaster recovery strategy requires a recovery time objective (RTO) and recovery point objective (RPO) within 30 minutes of failure. You plan to use a Google Cloud managed service. What should you do to maximize uptime for your application?

Answer options

• A. Deploy Cloud SQL for PostgreSQL in a regional configuration. Create a read replica in a different zone in the same region and a read replica in another region for disaster recovery.
• B. Deploy Cloud SQL for PostgreSQL in a regional configuration with HA enabled. Take periodic backups, and use this backup to restore to a new Cloud SQL for PostgreSQL instance in another region during a disaster recovery event.
• C. Deploy Cloud SQL for PostgreSQL in a regional configuration with HA enabled. Create a cross-region read replica, and promote the read replica as the primary node for disaster recovery.
• D. Migrate the PostgreSQL database to multi-regional Cloud Spanner so that a single region outage will not affect your application. Update the schema to support Cloud Spanner data types, and refactor the application.

Correct answer: C

Explanation

The correct answer is C because deploying Cloud SQL for PostgreSQL with HA and creating a cross-region read replica ensures that the application can quickly recover from a disaster with minimal downtime. Option A is insufficient since it only has a read replica in a different zone, which does not guarantee high availability. Option B relies on periodic backups, which may not meet the RTO and RPO requirements. Option D involves a more complex migration to Cloud Spanner, which is not necessary to achieve high availability for PostgreSQL.