Method and apparatus for managing the dynamic assignment resources in a data storage system

A storage system, comprising:

• at least first and second storage devices;
• at least first and second controllers, each one of the controllers capable of controlling at least one storage device and having a set of ports connectable to the at least one storage device and through which the one of the controllers can be configured to control the at least one storage device, wherein the set of ports for the first controller and the set of ports for the second controller each include at least one port;
• and
• a memory that is globally accessible to each of the plurality of controllers, the memory including a global table that stores information that specifies dynamic assignments of resources to which the first and second controllers control access;
• wherein at least one of the first and second controllers includes a local table that includes all of the information stored in the global table;
• wherein the first storage device is coupled to at least one of the set of ports for the first controller so as to permit the first controller to control access to the first storage device;
• wherein the first storage device is not coupled to the second controller in a manner that would permit the second controller to control access to the first storage device, so that the second controller cannot control access to the first storage device;
• wherein the second storage device is coupled to at least one of the set of ports for the second controller so as to permit the second controller to control access to the second storage device;
• and
• wherein the second storage device is not coupled to the first controller in a manner that would permit the first controller to control access to the second storage device, so that the first controller cannot control access to the second storage device.

A method of managing dynamic assignments of resources in a storage system including at least first and second storage devices and at least first and second controllers, each one of the controllers capable of controlling at least one storage device and having a set of ports connectable to the at least one storage device and through which the one of the controllers can be configured to control the at least one storage device;

• wherein the first storage device is coupled to at least one of the set of ports for the first controller so as to permit the first controller to control access to the first storage device;
• wherein the first storage device is not coupled to the second controller in a manner that would permit the second controller to control access to the first storage device, so that the second controller cannot control access to the first storage device;
• wherein the second storage device is coupled to at least one of the set of ports for the second controller so as to permit the second controller to control access to the second storage device;
• wherein the second storage device is not coupled to the first controller in a manner that would permit the first controller to control access to the second storage device, so that the first controller cannot control access to the second storage device;
• wherein the set of ports for the first controller and the set of ports for the second controller each include at least one port;
• and
• wherein the storage system further includes a memory that is globally accessible to each of the first and second controllers, the first and second controllers controlling the dynamic assignments of resources based upon information stored within the first and second controllers;
• the method comprising steps of:
• (A) creating a global table, in the memory, that stores information concerning all the dynamic assignments of resources in the storage system;
• (B) creating a local table in each of the first and second controllers that includes all of the information stored in the global table;
• and
• (C) controlling the dynamic assignments of resources based upon the information in the local tables.

A storage system comprising:

• at least first and second storage devices;
• at least first and second controllers, each one of the controllers capable of controlling at least one storage device and having a set of ports connectable to the at least one storage device and through which the one of the controllers can be configured to control the at least one storage device, wherein the set of ports for the first controller and the set of ports for the second controller each include at least one port, each of the first and second controllers including a local memory to store a local table that includes information that specifies dynamic assignments of resources in the storage system;
• and
• a memory to store a global table that stores information that specifies the dynamic assignments of resources in the storage system, the memory being accessible by each of the first and second controllers;
• wherein each one of the first and second controllers includes updating means, responsive to the one of the first and second controllers being powered up, for automatically updating the local table in the one of the first and second controllers based upon the information stored in the global table;
• wherein the first storage device is coupled to at least one of the set of ports for the first controller so as to permit the first controller to control access to the first storage device;
• wherein the first storage device is not coupled to the second controller in a manner that would permit the second controller to control access to the first storage device, so that the second controller cannot control access to the first storage device;
• wherein the second storage device is coupled to at least one of the set of ports for the second controller so as to permit the second controller to control access to the second storage device;
• wherein the second storage device is not coupled the first controller in a manner that would permit the first controller to control access to the second storage device, so that the first controller cannot control access to the second storage device;
• and
• wherein the storage system includes determination means for determining which of the local tables within the first and second controllers was updated most recently.

A method of managing dynamic assignments of resources in a storage system including at least first and second storage devices and at least first and second controllers, each one of the controllers capable of controlling at least one storage device and having a set of ports connectable to the at least one storage device and through which the one of the controllers can be configured to control the at least one storage device;

• wherein the first storage device is coupled to at least one of the set of ports for the first controller so as to permit the first controller to control access to the first storage device;
• wherein the first storage device is not coupled to the second controller in a manner that would permit the second controller to control access to the first storage device, so that the second controller cannot control access to the first storage device;
• wherein the second storage device is coupled to at least one of the set of ports for the second controller so as to permit the second controller to control access to the second storage device;
• wherein the second storage device is not coupled to the first controller in a manner that would permit the first controller to control access to the second storage device, so that the first controller cannot control access to the second storage device;
• wherein the set of ports for the first controller and the set of ports for the second controller each include at least one port, the first controller being arranged to control the dynamic assignments of resources based upon information stored within a first table in the storage system;
• and
• wherein the storage system further includes a second table including information specifying the dynamic assignments of resources to which the first and second controllers control access;
• the method comprising a step of:
• (A) verifying that the information stored within the first table accurately reflects the dynamic assignments of resources to which the first and second controllers control access by comparing the information stored within the first table with the information stored within the second table.

A storage system, comprising:

• at least first and second storage devices;
• at least first and second dynamic assignment tables that each includes information specifying dynamic assignments of resources in the storage system;
• at least first and second controllers, each one of the controllers capable of controlling at least one storage device and having a set of ports connectable to the at least one storage device and through which the one of the controllers can be configured to control the at least one storage device, wherein the set of ports for the first controller and the set of ports for the second controller each include at least one port, wherein the first controller is arranged to control the dynamic assignments of resources based upon the information stored within the first dynamic assignment table, and wherein the information included in the second dynamic assignment table specifies the dynamic assignments of resources to which the first and second controllers control access;
• and
• verification means for verifying that the information stored within the first dynamic assignment table accurately reflects the dynamic assignments of resources to which the first and second controllers control access by comparing the information stored within the first dynamic assignment table with the information stored within the second dynamic assignment table;
• wherein the first storage device is coupled to at least one of the set of ports for the first controller so as to permit the first controller to control access to the first storage device;
• wherein the first storage device is not coupled to the second controller in a manner that would permit the second controller to control access to the first storage device, so that the second controller cannot control access to the first storage device;
• wherein the second storage device is coupled to at least one of the set of ports for the second controller so as to permit the second controller to control access to the second storage device;
• and
• wherein the second storage device is not coupled to the first controller in a manner that would permit the first controller to control access to the second storage device, so that the first controller cannot control access to the second storage device.

A method for managing dynamic assignments of resources in a storage system including at least first and second controllers, each one of the controllers capable of controlling at least one storage device and having a set of ports connectable to the at least one storage device and through which the one of the controllers can be configured to control the at least one storage device;

• wherein the first storage device is coupled to at least one of the set of ports for the first controller so as to permit the first controller to control access to the first storage device;
• wherein the first storage device is not coupled to the second controller in a manner that would permit the second controller to control access to the first storage device, so that the second controller cannot control access to the first storage device;
• wherein the second storage device is coupled to at least one of the set of ports for the second controller so as to permit the second controller to control access to the second storage device;
• wherein the second storage device is not coupled to the first controller in a manner that would permit the first controller to control access to the second storage device, so that the first controller cannot control access to the second storage device;
• and
• wherein the set of ports for the first controller and the set of ports for the second controller each include at least one port, each of the first and second controllers having a local memory that stores information specifying the dynamic assignments of resources of the storage system;
• the method comprising the steps of:
• (A) identifying which one of the first and second controllers has stored in its local memory a most current version of the information specifying the dynamic assignments of resources;
• and
• (B) using the contents of the local memory of the one of the first and second controllers identified in step (A) to update the contents of the local memory of the other of the first and second controllers.

A method for managing dynamic assignments of resources in a storage system including at least first and second storage devices and at least first and second controllers, each one of the controllers capable of controlling at least one storage device and having a set of ports connectable to the at least one storage device and through which the one of the controllers can be configured to control the at least one storage device;

• wherein the first storage device is coupled to at least one of the set of ports for the first controller so as to permit the first controller to control access to the first storage device;
• wherein the first storage device is not coupled to the second controller in a manner that would permit the second controller to control access to the first storage device, so that the second controller cannot control access to the first storage device;
• wherein the second storage device is coupled to at least one of the set of ports for the second controller so as to permit the second controller to control access to the second storage device;
• wherein the second storage device is not coupled to the first controller in a manner that would permit the first controller to control access to the second storage device, so that the first controller cannot control access to the second storage device;
• and
• wherein the set of ports for the first controller and the set of ports for the second controller each include at least one port;
• the method comprising the steps of:
• (A) creating first and second copies of a table that specifies the dynamic assignments of dynamically assigned resources associated with the first storage device and the dynamic assignments of dynamically assigned resources associated with the second storage device;
• (B) storing the first copy of the table in a local memory of the first controller;
• and
• (C) storing the second copy of the table in a local memory of the second controller.

A method for managing dynamic assignments of resources in a storage system including at least first and second storage devices and at least first and second controllers, each one of the controllers capable of controlling at least one storage device and having a set of ports connectable to the at least one storage device and through which the one of the controllers can be configured to control the at least one storage device;

• wherein the first storage device is coupled to at least one of the set of ports for the first controller so as to permit the first controller to control access to the first storage device;
• wherein the first storage device is not coupled to the second controller in a manner that would permit the second controller to control access to the first storage device, so that the second controller cannot control access to the first storage device;
• wherein the second storage device is coupled to at least one of the set of ports for the second controller so as to permit the second controller to control access to the second storage device;
• wherein the second storage device is not coupled to the first controller in a manner that would permit the first controller to control access to the second storage device, so that the first controller cannot control access to the second storage device;
• and
• wherein the set of ports for the first controller and the set of ports for the second controller each include at least one port, and each having a respective local memory that stores information specifying the dynamic assignments of resources of the storage system;
• the method comprising a step of:
• (A) storing in the local memory of the first controller information reflecting the dynamic assignment of resources to which the second controller controls access.