Hardware and software faults

Last but not least, some field problems with appliances occur because of software and hardware faults. Unlike the other causes of field problems discussed above, faults are the result of some bug in the system's implementation, and usually result in system down-time. For a mature system made by a technically sound organization, the number of field disruptions due to faults should be very small.

Field problems due to faults are not discussed further in this paper. The techniques that we describe in this paper to enable easy debugging of field problems may have some applicability to diagnosing certain types of field disruptions due to faults, but in this paper we restrict our focus to diagnosing configuration and capacity problems.