RPO and RTO
The recovery point objective (RPO) is the most recent data you can afford to lose in a disaster, measured as time before the failure. The recovery time objective (RTO) is the longest the service can stay down before it must work again. Together they decide how much backup, replication, and standby capacity a system needs.
Reliability
In Quorum#
A Database's backups set its RPO: None loses everything, Nightly up to 1,440 calendar minutes, and PITR (Point-in-time recovery research) 2 minutes. A Read Replica in another region lowers it to that replica's lag, and a spread Wide-column Store or Distributed SQL loses nothing. The IPO checklist's DR drill fails the home region and passes only when errors fall under 1% within 60 calendar minutes (RTO) and the RPO is under 5 minutes.
Read next#
Point-in-time recovery, Synchronous replication, Availability zone, MTTR