Disaster Recovery (DR) & Metrics, Recovery, Testing, and Systems

MTBF

Mean Time Between Failures; This measures the average amount of time a machine or system works properly before it breaks down and needs to be repaired. For example, if an office printer runs for 2,000 hours and breaks down twice, its MTBF is 1,000 hours, meaning you can usually expect it to work for 1,000 hours between repairs.

MTTF

Mean Time To Failure; This measures how long a part is expected to last before it breaks completely and cannot be fixed and thrown away.

MTTR

Mean Time To Repair; This is the average amount of time it takes to fix a broken system and get it working normally again.

RPO

Recovery Point Objective; This defines the maximum amount of data a company can afford to lose if a disaster happens, measured in time.

RTO

Recovery Time Objective; This is the absolute longest amount of time a system is allowed to stay broken before it causes a major disaster for the business. If your laptop dies right before a big class presentation, your RTO might be 15 minutes, the exact amount of time you have to quickly switch to a backup computer before presenting.

Technical simulation

Is a practice run where a team purposely creates a specific computer problem, like a broken connection or a cloud service crash, in a safe and controlled setting. After creating the fake problem, the team practices following their step-by-step recovery plan to fix it. They measure exactly how long it takes to get everything working again to see if they can meet their goal for how fast they are supposed to recover.

Tabletop exercises

Is a discussion-based practice where a team sits down and talks through a fake emergency. Instead of touching any computer systems, the key people discuss what strategies they would use, how they would talk to each other, and what decisions they would make if a disaster actually happened.

MQTT broker

Is a system that handles sending and receiving messages between different smart devices. It is critical to recovery planning because it is considered an essential part of how the whole system operates as devices rely on it to talk to each other.

Cloud backend

Is the internet-based server system that stores databases, manages device settings, and passes commands between your mobile app and your smart gadgets. It is critical to recovery planning because a cloud crash can stop important services from working, such as locking users out of their smart home apps.

IoT gateways

Is a connection point that links local smart devices to the larger network or the cloud. It is critical to recovery planning because a broken gateway can be a "single point of failure," meaning every device connected to it will immediately lose its network connection.