A high-performance, high-reliable backplane bus has a simple configuration and operation. An error reporting network (ERN) provides an inexpensive approach to collecting the error state of a whole system in a uniform and consistent way. The uniformity allows for simpler interface software and for standardized hardware handling of classes of errors. In a preferred embodiment, serial error registers are used, minimizing implementation cost and making the software interface to the serial registers much easier. Serial error information is transferred over a separate data path from the main parallel bus, decreasing the chance of the original error corrupting the error information. Each CPU is provided with a local copy of the entire body of error information. The redundancy minimizes the impact of a possible CPU failure and allows the CPUs to coordinate error recovery.