Lab8: Test Fault Tolerance

An Aurora DB cluster is fault tolerant by design. The cluster volume spans 3 Availability Zones in a single AWS Region, and each Availability Zone contains 2 copies of the data. This functionality means that your DB cluster can tolerate a failure of an Availability Zone without any loss of data and only a brief interruption of service.

If the primary instance in a DB cluster using single-master replication fails, Aurora automatically fails over to a new primary instance in one of two ways:

  1. By promoting an existing Aurora Replica to the new primary instance
  2. By creating a new primary instance

In this lab, we will simulate a failover of the Aurora PostgreSQL cluster, and observe the change in writer and reader roles. This lab contains the following tasks:

  1. Set up failover event notifications
  2. Test a manual DB cluster failover
  3. Testing fault injection queries
  4. Use RDS Proxy to minimize failover disruptions

Prerequisites

This lab requires the following lab modules to be completed first: