In the previous section, you learned about using high availability and fault tolerance to handle application uptime. There may be a situation when the entire region where your data center is located goes down due to massive power grid outages, earthquakes, or floods, but your global business should continue running. In such situations, you must have a disaster recovery plan where you will plan your business continuity by preparing sufficient IT resources in an entirely different region, maybe in different continents or countries.

When planning disaster recovery, a solution architect must understand an organization's Recovery Time Objective (RTO) and Recovery Point Objective (RPO). RTO means how much downtime a business can sustain without any significant impact. RPO indicates how much data loss a business can resist. A reduced RTO and RPO means more cost, so it is essential to understand whether the business is mission-critical and needs...