Regardless of the level of deliberate work or automation involved in implementing a DR strategy, it's still important to verify that recovered workloads are functioning normally. Administrators should compare the performance of workloads operating in a DR state against the performance of those same workloads operating under normal conditions.
Application monitoring tools, such as Amazon CloudWatch and Google Stackdriver, look at workload health. These tools also collect logs, metrics and events that relay operational data about the recovered workloads. Additionally, they continue to monitor the workload's performance and availability throughout the cloud outage.