What is the Recovery Time Objective (RTO) of Elastic Disaster Recovery?
The Recovery Time Objective (RTO) of Elastic Disaster Recovery is typically measured in minutes. The RTO is highly dependent on the OS boot time.
A: When launching a recovery job, the AWS DRS orchestration process creates cloned volumes by using the replicated volumes in the replication staging area. During this process, AWS DRS also initiates a process that converts all volumes that originated outside of AWS into AWS-compatible volumes, which are attached to EC2 instances that can boot natively on AWS. The job and boot time depend on the following environment conditions:
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OS type: The average recovered Linux server normally boots within 5 minutes, while the average recovered Windows server normally boots within 20 minutes because it is tied to the more resource-intensive Windows boot process.
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OS configuration: The OS configuration and application components it runs can impact the boot time. For example, some servers run heavier workloads and start additional services when booted, which may increase their total boot time.
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Target instance performance: AWS DRS sets a default instance type based on the CPU and RAM provisioned on the source server. Changing to a lower performance instance type will result in a slower boot time than that of a higher performance instance type.
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Target volume performance: Using a lower performance volume type will result in a slower boot time than that of a higher performance volume type with more provisioned IOPS.
