Storage control apparatus and method of controlling storage control apparatus

A method of controlling a storage control apparatus controlling data input/output between a host computer and a storage unit, the storage control apparatus having

• a first communication part for communicating with the host computer and storing an allocation table for allocating commands issued by the host computer;
• a second communication part for communicating with the storage unit on which a plurality of logical volumes are managed;
• a plurality of microprocessors for controlling the data input/output between the host computer and the storage unit by using the first communication part and the second communication part;
• a shared memory used by each of the microprocessors;
• and
• a plurality of local memories arranged for the microprocessors respectively,
• where a first microprocessor of the microprocessors:
• corresponds to an use authority of a first logical volume and a second logical volume;
• executes a process of a command relating to the first logical volume and a command relating to the second logical volume by referring to first configuration information and second configuration information stored in a first local memory, arranged for the first microprocessor, of the local memories, the first configuration information relating to the first logical volume, the second configuration information relating to the second logical volume,
• where a second microprocessor of the microprocessors:
• corresponds to an use authority of a third logical volume;
• executes a process of a command relating to the third logical volume by referring to third configuration information in a second local memory, arranged for the second microprocessor, of the local memories, the third configuration information relating to the third logical volume,
• where the shared memory stores the first configuration information, the second configuration information and the third configuration information,
• each of the local memories further stores use authority information representing authority to use each of the logical volumes,
• in the use authority information, reception authority information representing authority to receive the commands relating to the logical volumes and execution authority information representing authority to process the commands using the logical volumes are associated with each other for each of the logical volumes beforehand,
• the method comprising:
• determining whether a predetermined condition is satisfied or not;
• when the predetermined condition is satisfied:
• moving the use authority of the first logical volume from the first microprocessor to the second microprocessor;
• deleting the first configuration information from the first local memory;
• copying the first configuration information stored in the shared memory to the second local memory;
• and
• executing, by the second microprocessor, a process of a command relating the first volume by referring to the first configuration information in the second local memory.