CLUSTERED CLIENT FAILOVER

• US 20130066941A1
• Filed: 09/09/2011
• Published: 03/14/2013
• Est. Priority Date: 09/09/2011
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Kruse, David M., Fathalla, Diaa, Pinkerton, James T., George, Mathew, Prahalad, Prashanth, Jolly, Thomas E.
• Granted Patent: US 8,788,579 B2
• Time in Patent Office: Days
• US Class Current: 709/203
• CPC Class Codes: H04L 67/10 in which an application is distributed across nodes in the network software deployment G06F8/60; multiprogramming arrangements G06F9/46
• CPC Class Codes: H04L 69/40 for recovering from a failure of a protocol instance or entity, e.g. service redundancy protocols, protocol state redundancy or protocol service redirection management of faults, events, alarms or notifications in data switching networks H04L41/06

Abstract

An application instance identifier is employed with various systems and methods in order to provide a requestor with continuous access to a resource when operating in a client clustered environment. A requestor residing on a first client in may attempt to access a resource. The first client sends a request to access the resource. The request may be associated with an application instance identifier that identifiers the requestor. At some point, the first client fails and the requestor is associated with a second client via a failover mechanism. The second client sends a second request to access the resource on behalf of the requestor. The second request is associated with the requestor'"'"'s application instance identifier. The application instance identifier is used to identify the second request as belonging to the same requestor as the first request, thereby granting the second request to access the resource while avoiding a conflict situation.

Claims

1. A method of providing continuous access to a resource, the method comprising:

receiving a first request to access a resource from a requestor, wherein the request is received from a first client;

associating a first application instance identifier with the first resource;

allowing the first request access to the resource;

receiving a second request for the resource from the requestor after recovering from a failure, wherein the second request is received from a second client different from the first client;

receiving a second application identifier associated with the second request;

determining if the first application identifier and the second application identifier are the same; and

when the first and second application identifiers are the same, performing the steps comprising;

invalidating the first request; and

granting the second request to access the resource.

2. The method of claim 1, wherein the first application identifier is associated with an application instance of an open request.

3. The method of claim 1, wherein the first application identifier is associated with a process.

4. The method of claim 1, wherein the first application identifier is associated with at least one child process of an application.

5. The method of claim 1, wherein the first request is received from a first node in the clustered environment.

6. The method of claim 5, wherein the second request is received from a second node in the clustered environment, and wherein the second node is different from the first node.

7. The method of claim 1, wherein retrieving the second application identifier comprises receiving the second application identifier from the requestor.

8. The method of claim 1, further comprising storing the first application identifier in a registry.

9. The method of claim 1, wherein invalidating the first request comprises determining if the resource is located on a first node that receives the second request.

10. The method of claim 9, further comprising:

when the resource is not located on the first node that receives the second request, performing the steps comprising;

sending a request to a second node to invalidate the first request, wherein the second node hosts the first request'"'"'s access to the resource; and

granting access the second request access to the resource on the first node.

11. The method of claim 1, wherein associating the first application instance identifier comprises receiving the first application instance identifier in a NETWORK_APP_INSTANCE_ECP_CONTEXT structure.

12. The method of claim 11, wherein the first application instance identifier in the NETWORK_APP_INSTANCE_ECP_CONTEXT structure is added to an ECP list.

13. A method for providing clustered client failover, the method comprising:

receiving, at a second client, an application instance identifier for a requestor, wherein the requestor previously accessed a resource using a first client;

sending, from the second client, a second request to access the resource on behalf of the requestor;

sending, from the second client, the application instance identifier for the requestor;

receiving an indication that a server granted the second request; and

accessing, by the second client, the resource on behalf of the client.

14. The method of claim 13, wherein the server granting the second request previously granted a first request to access the resource from the first client on behalf of the requestor.

15. The method of claim 13, wherein the second client sends the second request in response to a client failover.

16. The method of claim 13, wherein the application instance identifier is sent by making a call to an API.

17. The method of claim 13, wherein the application instance identifier is sent using a kernel level interface.

18. A system for facilitating client failover in a clustered environment, the system comprising:

at least one server comprising;

at least one processor configured to execute computer executable instructions;

at least one computer readable storage media storing the computer executable instructions that when executed by the at least one processor provide;

receiving a first request to access a resource from a first client on behalf of a requestor;

associating a first application instance identifier with the first resource;

allowing the requestor access to the resource;

receiving a second request for the resource from a second client, wherein the second client is different from the first client;

receiving a second application identifier associated with the second request;

determining if the first application identifier and the second application identifier are the same;

when the first and second application identifiers are the same, performing the steps comprising;

invalidating the first request; and

granting the second request to access the resource.

19. The system of claim 18, wherein the system further comprises:

the first client, comprising;

at least one processor configured to execute computer executable instructions;

at least one computer readable storage media storing the computer executable instructions that when executed by the at least one processor;

sending the first request;

sending the application instance identifier to a second client.

20. The system of claim 19, wherein the system further comprises:

the first client, comprising;

at least one processor configured to execute computer executable instructions;

at least one computer readable storage media storing the computer executable instructions that when executed by the at least one processor;

receiving the application instance identifier from the first client; and

sending the second request to access the resource with the application instance identifier.