Question

Difficulty: HardDatabase High Availability

An organization hosts a multi-tier web application using an Amazon Aurora MySQL Global Database. The primary DB cluster is in the us-east-1 Region, and a secondary DB cluster is in the us-west-2 Region for disaster recovery. A SysOps Administrator is tasked with designing a failover mechanism so that if the primary Region becomes completely unavailable, application traffic is redirected to us-west-2 with minimal downtime. The database in us-west-2 must be capable of accepting write traffic. Which configuration should the SysOps Administrator implement to achieve this goal?

  1. A
    Configure an Amazon Route 53 failover routing policy with the primary cluster's writer endpoint as primary and the secondary cluster's reader endpoint as secondary. Aurora Global Database will automatically promote the secondary cluster to a writer and update the Route 53 record when the primary Region becomes unhealthy.
  2. Configure an Amazon Route 53 failover routing policy pointing to the primary cluster's writer endpoint. Create a Route 53 health check that monitors the primary database. Configure an AWS Lambda function triggered by the health check failure to promote the secondary Aurora DB cluster in us-west-2 to a standalone primary cluster.Answer
  3. C
    Configure Route 53 latency-based routing with active-active configuration. Configure both Aurora DB clusters in us-east-1 and us-west-2 as primary writers to allow the application to write to either Region, while Route 53 automatically stops routing to the failed Region.
  4. D
    Create a Route 53 CNAME record pointing to the cross-region read replica in us-west-2. During an outage in the primary Region, Aurora will automatically perform a synchronous failover to the replica, allowing it to begin accepting write traffic without manual intervention.

Answer

To configure failover for an Amazon Aurora MySQL Global Database, you must set up a Route 53 failover routing policy to detect primary region failure, and configure an AWS Lambda function triggered by the Route 53 health check failure to promote the secondary Aurora DB cluster in the disaster recovery region to a standalone primary cluster.
The correct configuration uses a Route 53 health check to detect primary database unavailability and triggers an AWS Lambda function to promote the secondary cluster in the disaster recovery region to a standalone database. Since Aurora Global Database does not automatically promote secondary regional clusters during a disaster, this automation is required to enable write access in the secondary region.

Step-by-Step Solution

1
Create an Amazon Route 53 health check targeting the primary Aurora DB cluster in the us-east-1 Region.
The health status of the primary database is actively monitored.
Route 53 needs a mechanism to detect when the primary region is experiencing an outage.
2
Configure an AWS Lambda function that is triggered when the Route 53 health check reports an unhealthy status.
Automated invocation of the promotion workflow is established.
Because Aurora Global Database does not support automatic cross-region failover, custom automation must invoke the AWS API to promote the secondary database.
3
Write the Lambda function to promote the secondary Aurora DB cluster in us-west-2 using the AWS SDK.
The secondary cluster is detached from the global database and promoted to a standalone writeable DB cluster.
This allows the secondary database to begin accepting write traffic from the application.
4
Configure Route 53 failover routing records to point the database DNS alias to the new primary writer endpoint in us-west-2 once failover is completed.
Application write traffic is dynamically redirected to the promoted database cluster.
To ensure minimal application downtime and restore database write capabilities automatically.

Key Concept

Amazon Aurora Global Database cross-region failover is an unplanned disaster recovery event that requires manual promotion of the secondary cluster to a standalone primary cluster. This promotion can be automated via AWS Lambda triggered by Route 53 health checks. In contrast, local Multi-AZ failovers within a single Region are fully managed and automatic.
Estimated Time:2m 30s
Rate this question