Question

Difficulty: MediumDeveloping Procedures for Business Continuity and Disaster Recovery Validation

An enterprise global supply chain platform hosts its primary database on Cloud SQL for PostgreSQL in `us-east4` with a cross-region read replica in `us-central1` to support disaster recovery (DR). The business mandates a recovery point objective (RPO) of under 5 minutes and a recovery time objective (RTO) of under 1 hour. Your team is designing an annual non-disruptive DR validation procedure to verify failover readiness and application functionality in `us-central1`. Which procedure should you incorporate into the validation plan to meet these requirements without risking production data integrity?

  1. Verify compute and storage resource quotas in `us-central1` ahead of the test, promote a isolated clone of the cross-region replica for validation testing, and test DNS traffic steering to the staging endpoint.Answer
  2. B
    Initiate an unannounced live promotion of the primary cross-region database replica to master status in `us-central1` and immediately update production Cloud DNS A records to route active customer traffic.
  3. C
    Execute the DR validation script using standard regional default quotas in `us-central1` and promote the standby replica directly during the test window.
  4. D
    Migrate the database to a multi-region HA Cloud VPN setup prior to testing to ensure continuous cross-region transactional consistency without needing replica promotion.

Answer

Verify compute and storage resource quotas in the target disaster recovery region prior to testing, create and promote a isolated clone of the read replica to test application functionality, and update DNS pointing to non-production staging endpoints.
Safe DR validation procedures require pre-verifying regional resource quotas to guarantee capacity in the secondary region. Using a database clone of the cross-region read replica for validation allows full write testing and application verification without disrupting live replication or introducing production risk.

Step-by-Step Solution

1
Audit target region quotas
Ensure Compute Engine and storage resource quotas in `us-central1` are sufficient to host failover workloads before initiating validation.
Quota limits can silently fail spin-up tasks during a failover drill.
2
Clone cross-region read replica
Create a point-in-time database clone from the `us-central1` cross-region read replica.
Promoting a clone preserves the active replication stream between `us-east4` and `us-central1` so production remains unaffected during validation.
3
Validate application logic and networking
Connect test application instances in `us-central1` to the cloned database and verify end-to-end operational readiness.
Ensures RTO and RPO validation criteria are met without impacting active production data.

Key Concept

Disaster Recovery Validation and Failover Testing Procedures
Rate this question