Mean time to repair
(also MTTR)
Mean time to repair definition
In the context of information technologies (IT), the mean time to repair is the average time it takes to repair an IT system after a failure. The lower the mean time to repair, the less downtime the organization can expect to suffer when an emergency occurs.
Mean time to repair is an important metric in IT service level agreements. By factoring in the mean time to repair, clients are able to anticipate the levels of downtime when planning for emergencies.
See also: mean time to recovery, mean time to respond, recovery time objective, cyber incident response plan, cyber incident, response time
Measuring the mean time to repair
The mean time to repair spans the length of time between when the repairs begin and the point at which the system has been completely restored. You calculate the mean time to repair by dividing the total repair time (also known as “corrective maintenance”) spent over the duration of a maintenance contract by the total number of failures.
Mean time to repair components
- Diagnosis: Time spent determining the root cause of the failure, including analyzing logs, examining configurations, and investigating dependencies.
- Repair: Time needed to fix the issue and restore the service to full functionality.
- Testing: Time spent on tests to make sure the service is functioning as expected after the repair. The IT technicians may need to try out different scenarios to finally approve the solution.