Apparatus and method to provide failover protection to a data storage and retrieval system

An accessor moveably disposed in a data storage and retrieval system, where that accessor includes an accessor controller, a work queue stored in the accessor controller, and an inventory stored in the accessor controller. Applicants' work queue comprises each work request provided to the data storage and retrieval system, and each work entry created by the accessor controller to perform a work request. Work requests may be received from attached host computer systems, from an operator input station, and/or from an import/export controller. A data storage and retrieval system which includes at least two of Applicant's accessors. A method to provide failover protection to Applicant's data storage and retrieval system in the event of a failure of one or more of Applicant's accessors.