A Fibre Channel switch has eight ports and all ports must be operational from 8 AM to 8 PM, Monday through Friday. However, a failure of Port 7 occurs in the week as follows:
Monday = 11 AM to 12 PM -
Wednesday = 4 PM to 9 PM -
Thursday = 4 AM to 9 AM -
Friday = 2 PM to 6 PM -
Saturday = 9 AM to 1 PM -
What is the availability of Port 7 in that week?
The switch must be operational for a total of 12 hours each day, from Monday to Friday, making the total operational hours for the week 60 hours (12 hours per day times 5 days). The downtime is as follows: Monday = 1 hour, Wednesday = 5 hours, Thursday = 5 hours, and Friday = 4 hours. The downtime for Saturday should not be considered as it is outside the required operation period. Summing up the downtimes: 1 + 5 + 5 + 4 = 15 hours. Therefore, the uptime is 60 hours minus 15 hours of downtime, which equals 45 hours. The availability is calculated as the ratio of uptime to the total operational hours, which is 45/60, equating to 75%.
C. 83.3% Total Operation: 12*5= 60 Downtime: 1 + 4 + 1 + 4 = 10 Uptime = 60 - 10 = 50 Availability = Uptime / (Uptime + Downtime) = 50 /(50+10) = 0.833 * 100 = 83.3%
Downtime is 15hrs, Uptime=45, so 75% is the correct answer
C is correct
Time =12*5=60 Downtime=1+5+5+4=15 (removed Saturday) Uptime=60-15=45 Availability=(45/(45+15))*100=75%
Time =12*5=60 Downtime=1+5+5+4=15 (removed saturday) Uptime=60-15=45 Availability=(45/(45+15))*100=75%
Time =12*5=60 Downtime=1+5+5+4+4=19 Uptime=60-19=41 Availability=(41/(41+19))*100=68.3%
Erratum : Time =12*5=60 Downtime=1+5+5+4=15 (removed saturday) Uptime=60-15=45 Availability=(45/(45+15))*100=75%
Answer is A 1+5+5+4=15 (Exclude Saturday) total operating hours is 60 45/60=75 %