System for updating an identity of a device in response to determining that a neighbor device has an identity different from one stored therein

摘要

Methods and associated apparatus for generating and maintaining a unique identity for an enclosure in a storage system. Where an enclosure compliant with storage industry standards is to maintain a unique identity, methods of the present invention are operable to coordinate use of redundant devices within the enclosure that serve, among other functions, to store and report the unique identity of the enclosure. The redundant devices (i.e., environmental service cards or modules) assure that the enclosure identity remains unique among such enclosures despite hot or cold swaps of the redundant devices among the several enclosures. A change number portion of the unique identity value stored in each of the redundant devices is updated (i.e., incremented) each time a change in the configuration of redundant devices is detected by the devices. An incumbent one of the redundant devices reports the unique identity for the enclosure in response to attached system requests. By assuring a unique identity is generated in each redundant device upon sensing any change in the configuration of the redundant devices, the methods and apparatus of the present invention assure a unique identity for the enclosure is maintained and reported regardless of device swap operations (hot or cold devices swaps).