Storage array network path impact analysis server for path selection in a host-based I/O multi-path system

• US 8,843,789 B2
• Filed: 05/21/2012
• Issued: 09/23/2014
• Est. Priority Date: 06/28/2007
• Status: Active Grant

• Current Assignee: Emc IP Holding Company LLC (Dell Technologies Inc.)
• Original Assignee: EMC Corporation (Dell Technologies Inc.)
• Inventors: Sandstrom, Harold M., Artzi, Amanuel Ronen, Bappe, Michael E., Raizen, Helen S., Zahavi, William Z.
• Primary Examiner(s): Riad, Amine
• Application Number:
  US13/476,072
• Publication Number:
  US 20120233494A1
• Time in Patent Office: 855 Days
• Field of Search: None
• US Class Current: 714/43
• CPC Class Codes: G06F 11/0727 in a storage system, e.g. in a DASD or network based storage system drivers for digital recording or reproducing units G06F3/06; circuits for error detection or correction within digital recording or reproducing units G11B20/18; for distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS], H04L67/1097
• CPC Class Codes: G06F 11/0766 Error or fault reporting or storing
• CPC Class Codes: G06F 11/079 Root cause analysis, i.e. error or fault diagnosis in a hardware test environment G06F11/22; in a software test environment G06F11/36
• CPC Class Codes: G06F 11/201 between storage system components

Abstract

Systems and methods are provided for selecting a path for an I/O in a storage area network. In one embodiment, a method comprises receiving path configuration information for paths associated with a host device connected to the storage area network, a listing of components within the storage area network, and a notification of a component failure within the storage area network. The method may also comprise correlating the received path configuration information, the received listing of components, and the received notification of component failure to determine one determine one or more paths associated with the host device affected by the component failure. The method may further comprise transmitting to the host device an alert for the one or more affected paths.

Claims

1. A method comprising:

providing a path management module coupled to a storage area network, the storage area network comprising a plurality of paths from a storage device to a host device and comprising a plurality of components on the plurality of paths;

receiving path configuration information for the plurality of paths, a listing of the plurality of components within the storage area network, and a notification of a failure of a first component of the plurality of components within the storage area network;

correlating the received path configuration information, the received listing of the components, and the received notification of the failure of the first component to determine one or more paths associated with the host device affected by the failure; and

selecting, using the path management module, an alternative one of the paths to avoid the failed first component.

2. The method of claim 1 wherein selecting, using the path management module, an alternative one of the paths to avoid the failed first component comprises selecting an alternative one of the paths to avoid a failed port on a.

3. The method of claim 1, further comprising, transmitting the received path configuration information using the path management module residing on the host device.

4. The method of claim 3, further comprising:

transmitting the received listing of components using a topology server coupled to the storage area network; and

transmitting the received notification of the failure using a root cause analysis server coupled to the storage area network.

5. The method of claim 4, combining functionalities of the topology server and the root cause analysis server into a single server.

6. The method of claim 1, further comprising using the received path configuration information in the form of initiator-target-LUN nexuses.

7. The method of claim 1, further comprising wherein the received path configuration information is logically grouped.

8. A system comprising:

a host device coupled to the storage area network, the storage area network comprising a plurality of paths from a storage device to a host device and comprising a plurality of components on the plurality of paths;

a path impact analysis server for receiving path configuration information associated with the host device, a listing of the plurality of components within the storage area network, and a notification of a failure of a first component of the plurality of components within the storage area network, wherein the path impact analysis server is configured to;

correlate the received path configuration information, the received listing of components, and the received notification of the failure of the first component to determine one or more paths associated with the host device affected by the failure; and

a path management module in the host to select an alternative one of the paths to avoid the first component.

9. The system of claim 8, wherein the plurality of components comprises a plurality of ports.

10. The system of claim 8, wherein the received path configuration information of the host device is transmitted by the path management module residing on the host device.

11. The system of claim 9, further comprising:

a topology server coupled to the storage area network and configured to transmit the received listing of the plurality of components; and

a root cause analysis server coupled to the storage area network and configured to transmit the notification of the failure.

12. The system of claim 11, wherein the functionalities of the path impact analysis server, the topology server, and the root cause analysis server are combined into one server.

13. The system of claim 8, wherein the received path configuration information is in the form of initiator-target-LUN nexuses.

14. The system of claim 8, wherein the received path configuration information is logically grouped.

15. An article comprising:

a non-transitory machine-readable medium that stores executable instructions to select a path for an I/O in a storage area network, the storage area network comprising a plurality of paths from a storage device to a host device and comprising a plurality of components on the plurality of paths, the instructions when executed by a machine causing a machine to;

receive path configuration information associated with the host device, a listing of the plurality of components within the storage area network, and a notification of a component failure of the first component of the plurality of components within the storage area network;

correlate the received path configuration information, the received listing of the plurality of components, and the received notification of the failure of the first component to determine one or more paths associated with the host device affected by the failure; and

select an alternative one of the paths to avoid the failed first component.

16. The article of claim 15, wherein the plurality of components comprises a plurality of ports.

17. The article of claim 15, wherein the received path configuration information of a host device is transmitted by a path management software residing on the host device.

18. The article of claim 16, wherein the received listing of the plurality of components is transmitted by a topology server coupled to the storage area network, and

wherein the received notification of component failure is transmitted by a root cause analysis server coupled to the storage area network.

19. The article of claim 15, wherein the received path configuration information is in the form of initiator-target-LUN nexuses.

20. The article of claim 15, wherein the received path configuration information is logically grouped.