Question Id : 18825 |
Context : UGC NET Computer Science Nov 2021 (Paper II)
A system has $99.99\%$ uptime and has a mean-time-between-failure of $1$ day. How fast does the system has to repair itself in order to reach this availability goal?
🎥 Video solution / Text Solution of this question is given below:
Availability formula is:
$Availability=\frac{MTBF}{MTBF+MTTR}$
Given,
$Availability=99.99\%=0.9999$
$MTBF=1$ day $=24\times60\times60=86400$ seconds
Now,
$0.9999=\frac{86400}{86400+MTTR}$
$86400+MTTR=\frac{86400}{0.9999}$
$MTTR=\frac{86400}{0.9999}-86400$
$MTTR\approx 8.64$ seconds
So, repair time should be approximately $9$ seconds.