Logic circuit that provides verification of signals used to interrupt server operation

A storage controller, comprising:

• one or more primary data transfer busses that couple the storage controller and a second storage controller with a plurality of data storage drives;
• a first state machine with an interface operable to communicate with a corresponding state machine of a second storage controller;
• a first serial bus interface operable to couple the first state machine to a first multiple-access serial bus, the first multiple-access serial bus coupled to a plurality of logic circuits each associated with and coupled to the respective plurality of data storage drives, each of the logic circuits further coupled to a second multiple-access serial bus that is coupled to the second storage controller, the first and second multiple-access serial busses being separate from the one or more primary data busses, the logic circuits configured to receive first and second signals from the storage controller and the second storage controller via the respective first and second multiple-access serial busses in response to coordination between the first state machine and the corresponding state machine, the logic circuits interrupting the operation of the respective drives if the first and second signals agree.