Understanding RPO, RTO and DynamoDB Point-in-Time Recovery for AWS Disaster Recovery

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This second part of an AWS high-availability series explains the two core recovery metrics: recovery point objective, the maximum tolerable data loss measured in time, and recovery time objective, the maximum tolerable downtime. The author stresses that these targets are business decisions rather than engineering ones, with engineers responsible for quantifying the cost of each option. It highlights the consequences of missing them, including SLA penalties, regulatory fines and reputational harm. The piece then introduces DynamoDB Point-in-Time Recovery, which continuously captures table changes so a table can be restored to nearly any second within a rolling window of up to 35 days.

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