MTTR: Mean Time To Recover (or Resolve)
Definition: The average time it takes to restore a system or product to normal operation after a failure or incident has been detected
How to Calculate: Sum of (Time to Recover for each incident) / Total number of incidents
Scenario: An E-commerce Website (Continued from MTTD)
- Incident: A critical bug prevents customers from adding items to their shopping cart.
- Incident Start Time: 10:00 AM (when the bug was deployed and started affecting users)
- Detection Time: We calculated an average MTTD of approximately 13.33 minutes. For simplicity in this MTTR example, let’s assume the incident was officially detected and confirmed by the operations team at 10:15 AM. This 10:15 AM mark is when the clock for MTTR typically starts ticking (from detection to resolution).
Here’s how MTTR would apply:
- Detection/Confirmation Time (MTTR Start):
- The operations team confirms the critical shopping cart bug at 10:15 AM. This is the point where they’ve identified the problem and begin actively working on a solution.
- Investigation and Diagnosis:
- The team immediately begins investigating. They identify the faulty code change, pinpoint the root cause, and formulate a rollback or hotfix plan.
- This process takes some time. Let’s say it’s 10:35 AM when they have a clear plan.
- Implementation of Fix:
- The development team quickly implements the rollback/hotfix.
- This involves code changes, testing in a staging environment, and then deploying to production.
- Let’s assume the fix is fully deployed and verified to be working correctly at 11:00 AM.
- Resolution Time (MTTR End):
- At 11:00 AM, the shopping cart functionality is fully restored, and customers can successfully add items and proceed to checkout again. The incident is marked as resolved.
Calculating MTTR for this example:
- Time of Resolution: 11:00 AM
- Time of Detection/Confirmation (Start of Resolution Effort): 10:15 AM
MTTR = Time of Resolution – Time of Detection/Confirmation MTTR = 11:00 AM – 10:15 AM MTTR = 45 minutes
Interpretation:
In this example, the Mean Time To Recover (MTTR) for the critical shopping cart bug was 45 minutes. This means, on average, it took 45 minutes from the moment the operations team detected and confirmed the problem until it was fully resolved and the e-commerce functionality was restored for users.
Why is a low MTTR crucial?
- Minimizes Downtime & Impact: The faster you recover, the less negative impact on user experience, revenue, and brand reputation.
- Boosts Customer Trust: Quick recovery demonstrates reliability and responsiveness.
- Reduces Costs: Prolonged incidents can lead to significant financial losses (lost sales, engineering hours spent on crisis management, potential customer refunds).
- Indicates Operational Efficiency: A consistently low MTTR reflects effective incident response protocols, skilled teams, and robust recovery tools (e.g., automated rollbacks, quick deployment pipelines)