Automatic Failover of Nodes of a Middle-Tier Layer

• US 20140164818A1
• Filed: 12/03/2013
• Published: 06/12/2014
• Est. Priority Date: 12/06/2012
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Jones, Robert C., Mandelli, Manuela, Wilson, Russell
• Granted Patent: US 9,246,754 B2
• Time in Patent Office: Days
• US Class Current: 714/4.11
• CPC Class Codes: G06F 16/2458 Special types of queries, e.g. statistical queries, fuzzy queries or distributed queries
• CPC Class Codes: H04L 41/0668 by dynamic selection of recovery network elements, e.g. replacement by the most appropriate element after failure
• 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

Method and system are provided for automatic failover between multiple nodes in a middle-tier layer between client applications and a back-end service. The method at a first node includes: receiving a request from a client application; determining that the first node cannot service the request successfully; forwarding the request from the first node to a second peer node; receiving a response at the first node on completion of the request by the second peer node; and forwarding the response from the first node to the client application. An original path of communication between the client application and the first node is maintained. The failover of the request from the first node to the second peer node is transparent to the client application. Nodes may be registered in a group, wherein a node in a group has awareness of other nodes in the group.

Claims

1. A method for automatic failover between multiple nodes in a middle-tier layer between client applications and a back-end service, comprising:

receiving, at a first node, a request from a client application;

determining that the first node cannot service the request successfully;

forwarding the request from the first node to a second peer node;

receiving a response at the first node on completion of the request by the second peer node; and

forwarding the response from the first node to the client application;

wherein an original path of communication between the client application and the first node is maintained; and

wherein failover of the request from the first node to the second peer node is transparent to the client application.

2. The method as claimed in claim 1, further comprising:

registering a node in a group, wherein the node has awareness of other nodes in the group.

3. The method as claimed in claim 2, wherein registering the node in the group includes:

registering the node'"'"'s availability and access details.

4. The method as claimed in claim 2, further comprising:

establishing dedicated connections between peer nodes in the group utilizing optimized links where available.

5. The method as claimed in claim 4, wherein establishing a connection is carried out on a lazy basis when first needed.

6. The method as claimed in claim 1, further comprising:

the first node obtaining details of a peer node from a group registry of available peer nodes.

7. The method as claimed in claim 6, wherein the first node selects a peer node based upon the availability of dedicated connections.

8. The method as claimed in claim 1, further comprising:

the first node requesting a peer node from a group registry of available peer nodes; and

the group registry selecting a peer node from available peer nodes based on a selection criteria.

9. The method as claimed in claim 1, wherein forwarding the request from the first node to the second peer node includes forwarding information in a correct form required to call the back-end service.

10. The method as claimed in claim 1, further comprising:

receiving, by a second peer node, a forwarded response from the first node;

carrying out the service request at a back-end service; and

responding to the first node with an outcome of the request.

11. The method as claimed in claim 10, wherein the second peer node carries out the service request at a different back-end service resource than a back-end service resource that the first node attempted to use.

12. The method as claimed in claim 1, wherein the middle-tier layer is a transaction gateway between client applications and multiple transaction servers.

24. A computer program product for automatic failover between multiple nodes in a middle-tier layer between client applications and a back-end service, the computer program product comprising:

a computer readable storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method according to claim 1.

25. A computer program stored on a computer readable medium and loadable into the internal memory of a digital computer, comprising software code portions, when said program is run on a computer, for performing the method of claim 1.

13. A system for automatic failover between multiple nodes in a middle-tier layer between client applications and a back-end service, comprising:

a middle-tier layer having multiple nodes registered in groups;

wherein a failover mechanism is provided to forward a request received at a first node from a client application to a second peer node registered in a same group as the first node;

wherein an original path of communication between the client application and the first node is maintained; and

wherein failover of the request from the first node to the second peer node is transparent to the client application.

14. A system as claimed in claim 13, wherein a middle-tier node operating as the first node comprises:

a client request receiving component configured to receive a request from a client application;

a request servicing failure component configured to determine that the first node cannot service the request successfully;

a first peer node forwarding component configured to;

forwarding the request from the first node to a second peer node;

receiving a response at the first node on completion of the request by the second peer node; and

forwarding the response from the first node to the client application.

15. The system as claimed in claim 14, wherein the middle-tier node can perform a role of the first node or the second peer node.

16. The system as claimed in claim 14, further comprising:

a registry mechanism configured to register a node in a group, wherein the node has awareness of other nodes in the group and for registering the node'"'"'s availability and access details.

17. The system as claimed in claim 16, wherein the registry mechanism includes a peer connection establishing component configured to establish dedicated connections between peer nodes in the group utilizing optimized links where available.

18. The system as claimed in claim 16, wherein the first node is configured to obtain details of a peer node from the registry mechanism.

19. The system as claimed in claim 17, wherein the peer connection establishing component selects a peer node based upon the availability of dedicated connections.

20. The system as claimed in one of claim 16, wherein the registry mechanism is configured to receive a request for a peer node from a first node and for selecting another peer node from available peer nodes based on a selection criteria.

21. The system as claimed in claim 14, wherein a middle-tier node includes a peer node request receiving component that is configured to:

receive a forwarded response from the first node;

carry out the service request at a back-end service; and

respond to the first node with an outcome of the request.

22. The system as claimed in claim 21, wherein the second peer node carries out the service request at a different back-end service resource than a back-end service resource that the first node attempted to use.

23. The system as claimed in claim 14, wherein the middle-tier layer is a transaction gateway between client applications and multiple transaction servers.