
How to Properly Calculate System Availability
Recently received a request for my opinion concerning the calculation of system availability using the classic formula
$$ \displaystyle \large A=\frac{MTBF}{MTBF+MTTR}$$
The work is to create a set of goals for various suppliers and contractors to achieve. The calculation values derive from vendor data sheets and available information concerning MTBF and MTTR. The project is in the design phase; thus, they do not have working systems available to measure actual availability.
How would you go about improving on this approach? [Read more…]