Dell EMC Associate – Information Storage and Management v5 — Question 74

An Ethernet switch has eight ports and all ports must be operational for 24 hours from Monday through Friday. However, failures of Port 6 occur within the week as follows:

Tuesday = 6 AM to 8 AM -

Thursday = 5 PM to 10 PM -

Friday = 7 AM to 9 AM -

What is the MTBF of Port 6?

Answer options

• A. 40 hours
• B. 37 hours
• C. 32 hours
• D. 30 hours

Correct answer: B

Explanation

The MTBF calculation considers the total operational hours minus the hours of failure. Port 6 fails for 6 hours total over the week, resulting in 120 hours of scheduled operation minus 6 hours of downtime, leading to an MTBF of 114 hours. Dividing this by the number of failures, we find the average time between failures to be 37 hours. The other options do not accurately reflect this calculation.