CompTIA Network+ Practice Test

What does MTBF (Mean Time Between Failures) measure?

1. Frequency of failures

2. Average uptime of systems

3. Predict the time between outages

4. Duration of maintenance windows

The correct answer is: Predict the time between outages

MTBF, or Mean Time Between Failures, is a crucial metric used to evaluate the reliability of a system or component. It specifically measures the average time expected between failures of a system during its operational phase. This is essential for understanding how often you can expect a system to fail, which directly relates to assessing the reliability and availability of the services it provides. By calculating MTBF, organizations can make informed predictions regarding when future outages are likely to occur, allowing them to plan maintenance, allocate resources effectively, and improve the design of their systems to increase uptime. Therefore, this metric is vital in proactive maintenance strategies and ensuring high availability in network and IT environments. The other options represent different aspects of system management but do not accurately capture the essence of MTBF. For instance, while the frequency of failures indicates how often failures occur, it is not what MTBF measures, as MTBF is focused on the time intervals between those failures rather than how many occur over a specific period. Similarly, the average uptime of systems is a related but distinct metric measuring how long a system is operational compared to its downtime. Duration of maintenance windows pertains to the scheduled times for conducting system maintenance, which again is not related to the metric of MTBF, as it neither