The present invention is a method and a system for dynamic mapping of a fiber channel loop ID in an ALPA loop. Based on reserved address information for the fiber channel system and a number of select ID bits for a slot ID, a dynamic drive mapping table is created. A unique address may be assigned to each drive and each controller in the ALPA loop. The created drive mapping table may be stored on logic decoding circuitry of an adaptor card coupled to each disk drive in the ALPA loop. When fiber channel loop ID signals are sent from a backplane, the fiber channel loop ID signals are translated into seven bits within an ALPA address range based on the dynamic drive mapping table. The converted signals may be sent to the disk drive coupled the adaptor card at boot up time.