A method for managing a storage system and an associated apparatus are provided. The method includes: providing at least one heartbeat monitoring path between a set of expander control circuits within an expansion module in the storage system, for transmitting at least one of a plurality of heartbeat monitoring signals for a set of management modules in the storage system, wherein the expansion module is utilized for installing a set of shared storage devices, and each shared storage device within the set of shared storage devices is coupled to the set of expander control circuits, to allow the set of management modules to control the set of shared storage devices through the set of expander control circuits, respectively; and performing heartbeat monitoring according to the plurality of heartbeat monitoring signals, for at least one of the set of management modules to perform high availability management on shared storage devices.