Storage system adapter and method of using same

• US 20020118685A1
• Filed: 02/28/2001
• Published: 08/29/2002
• Est. Priority Date: 02/28/2001
• Status: Active Grant

• Current Assignee: Emc IP Holding Company LLC (Dell Technologies Inc.)
• Original Assignee: EMC Corporation (Dell Technologies Inc.)
• Inventors: Linnell, Thomas, Touch, Steven
• Granted Patent: US 7,082,100 B2
• Time in Patent Office: Days
• US Class Current: 370/400
• CPC Class Codes: G06F 3/0613 in relation to throughput
• CPC Class Codes: G06F 3/0635 by changing the path, e.g. traffic rerouting, path reconfiguration
• CPC Class Codes: G06F 3/0658 Controller construction arrangements
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]

Abstract

In one embodiment of the present invention, an adapter device is provided that may be used in a data storage system to permit data communication among host computer nodes external to the system and data storage system processors. The adapter device of this embodiment includes two or more network nodes configured to provide at least one network. The network may be used to interconnect the host computer nodes and the processors so as to permit the data communication among the host computer nodes and the processors. At least one of the network nodes is configurable so as to change the topology of the network. When the network'"'"'s topology is changed in this manner, the nature of the data communication permitted by the network among at least certain of the processors and the host computer nodes is also changed.

Claims

1. Adapter that may be used in a data storage system to permit data communication among data exchanging devices and data storage system processors, the processors residing in the data storage system, the data exchanging devices being external to the adapter, the adapter comprising:

a plurality of network nodes, the network nodes being configured to provide at least one network that may be used to interconnect the data exchanging devices and the processors so as to permit the communication among the data exchanging devices and the processors, at least one of the network nodes being configurable so as to change a topology of the network from at least one topology to at least one other topology, the communication permitted by the network among at least certain of the processors and the data exchanging devices being different depending upon which of the one topology and the other topology the network has.

2. Adapter according to claim 1 wherein when the network has the one topology, the network permits one of the processors to communicate only with a first subset of the devices, and when the network has the other topology, the network permits the one of the processors to communicate with a second subset of the devices, the first and second subsets having respective numbers of the devices equal to M and N, respectively, where M is less than N.

3. Adapter according to claim 2, wherein N is twice M.

4. Adapter according to claim 1, wherein the network comprises at least one fibre channel (FC) arbitrated loop network.

5. Adapter according to claim 4, further comprising at least one optical transceiver that may be used in coupling at least one host computer node to the network.

6. Adapter according to claim 2, wherein when the network has the one topology, the network permits another of the processors to communicate with a third subset of the devices, and when the network has the other topology, the network permits the another of the processors to communicate with the second subset of the devices, the third subset of the devices being different from the first subset of the devices.

7. Adapter according to claim 6, wherein the one and the another of the processors reside on a single circuit board, the board being connectable to the adapter so as to couple the one and the another of the processors to the network.

8. Adapter according to claim 6, wherein when the network has the one topology, the network comprises two network loops, and when the network has the other topology, the at least one of the network nodes connects the two loops so as to form a single logical loop.

9. Computer-readable memory comprising executable computer program instructions that when executed cause:

configuring of at least one network node in a network comprising a plurality of network nodes, the network nodes being comprised in an adapter that may be used in a data storage system to permit data communication among data exchanging devices and data storage system processors residing in the data storage system, the devices being external to the adapter, the configuring of the at least one network node changing a topology of the network from at least one network topology to at least one other network topology, the communication permitted by the network among at least certain of the processors and the devices being different depending upon which of the one topology and the other topology the network has.

10. Memory according to claim 9, wherein when the one network has the one topology, the network permits one of the processors to communicate only with a first subset of the devices, and when the network has the other topology, the network permits the one of the processors to communicate with a second subset of the devices, the first and second subsets having respective numbers of devices equal to M and N, respectively, where M is less than N.

11. Memory according to claim 10, wherein N is twice M.

12. Memory according to claim 9, wherein the network comprises at least one fibre channel (FC) arbitrated loop network.

13. Memory according to claim 12, wherein at least one optical transceiver is comprised in the adapter that may be used in coupling at least one host computer node to the network.

14. Memory according to claim 10, wherein when the network has the one topology, the network permits another of the processors to communicate with a third subset of the devices, and when the network has the other topology, the network permits the another of the processors to communicate with the second subset of the devices, the third subset of the devices being different from the first subset of the devices.

15. Memory according to claim 14, wherein the one and the another of the processors reside on a single circuit board, the board being connectable to the adapter so as to couple the one and the another of the processors to the network.

16. Memory according to claim 14, wherein when the network has the one topology, the network comprises two network loops, and when the network has the other topology, the at least one network node connects the two loops so as to form a single logical loop.

18. Method according to claim 17, wherein when the one network has the one topology, the network permits one of the processors to communicate only with a first subset of the devices, and when the network has the other topology, the network permits the one of the processors to communicate with a second subset of the devices, the first and second subsets having respective numbers of devices equal to M and N, respectively, where M is less than N.

19. Method according to claim 18, wherein N is twice M.

20. Method according to claim 17, wherein the network comprises at least one fibre channel (FC) arbitrated loop.

21. Method according to claim 26, further comprising providing in the adapter at least one optical transceiver that may be used in coupling the at least one host computer node to the network.

22. Method according to claim 18, wherein when the network has the one topology, the network permits another of the processors to communicate with a third subset of the devices, and when the network has the other topology, the network permits the another of the processors to communicate with the second subset of the devices, the third subset of the devices being different from the first subset of the devices.

23. Method according to claim 22, wherein the one and the another of the processors reside on a single circuit board, the board being connectable to the adapter so as to couple the one and the another of the processors to the network.

24. Method according to claim 22, wherein when the network has the one topology, the network comprises two network loops, and when the network has the other topology, the at least one network node connects the two loops so as to form a single logical loop.

17. Method of using an adapter in a data storage system to permit data communication among data exchanging devices and data storage system processors, the processors residing in the data storage system, the devices being external to the adapter, the method comprising the steps of:

configuring at least one network node in a network comprising a plurality of network nodes in the adapter, the configuring of the at least one network node changing a topology of the network from at least one network topology to at least one other network topology, the communication permitted by the network among at least certain of the processors and the devices being different depending upon which of the one topology and the other topology the network has.