RPO and RTO

Recovery Point Objective (RPO) is the maximum amount of data loss an organization tolerates, expressed in time: an RPO of 15 minutes means you must be able to restore to a state no older than 15 minutes before the failure. Recovery Time Objective (RTO) is the maximum tolerable time to restore service after a disruption.

The two numbers drive architecture and cost together. Tight RPOs require frequent replication or continuous backup (synchronous or near-synchronous copies); tight RTOs require pre-provisioned standby capacity and rehearsed failover. Every reduction in either number usually buys more infrastructure and more operational complexity.

State both numbers in writing, test against them at least annually with real failover exercises, and let them decide the design — not the other way around. A five-minute RPO achieved by accident is worth less than a documented four-hour RPO that has actually been demonstrated.