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Exploiting the Automatic Client Reconnect feature introduced in WebSphere MQ 7.0.1 – MQI (C Code)

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Abstract

The objective of this techdoc is to show real examples that use MQI (C Code) that exploit the new feature introduced in WebSphere MQ 7.0.1: Automatic Client Reconnect.

There are several mechanisms that specify how a client will do the automatic reconnection. This is the order of reconnection:

1) MQCNO flags for MQCONN – this is not shown in this document (these flags are specified inside an application).

2) If MQSERVER is present, then it is used. It overrides all the options 3 and 4.

3) If the MQSERVER is NOT present, then the next option is to use the Client Configuration File (mqclient.ini).

4) Finally, if none of the above is defined, then the CCDT is used.

+++ Table of Contents +++

Chapter 1: Setup of queue managers and clients

Chapter 2: Using the “High availability sample programs” (C code) – single queue manager
Scenario 2-A) Testing reconnect to a single standalone queue manager (using CCDT file)
Scenario 2-B) Testing reconnect to a single standalone queue manager (using MQSERVER)
Scenario 2-C) Testing reconnect to a single standalone queue manager (using client configuration file)

Chapter 3: Using the “High availability sample programs” (C code) – 2 separate queue managers
Scenario 3-A) Testing reconnect to another standalone queue manager (using MQSERVER) – Failure of sample with sync point
Scenario 3-B) VARIATION of Scenario 3-A: Using only the put and get samples (no sync point)
Scenario 3-C) Testing reconnect to another standalone queue manager, no sync point (using client configuration file)

Chapter 4: Using the “High availability sample programs” (C code) – multi-instance queue managers

Chapter 5: Behavior of clients that are not explicitly enabled for automatic reconnect (using client configuration file)
Scenario 5-A) Testing reconnect to another standalone queue manager, amqsputc and amqsgetc (C-code), MQ 7.0.1
Scenario 5-B) Testing reconnect to another standalone queue manager, amqsputc and amqsgetc (C-code), MQ 6

Appendix A: Troubleshooting

Appendix B: Information about the MQ Client Configuration File

Content

For details, see the attached PDF file:

MQ_701_Automatic_Client_Reconnect-C-code.pdf


Related information

WSTE: Exploiting the Automatic Client Reconnect feature

PDF File: MQ_701_Automatic_Client_Reconnect-C-code.pdf

MQ_701_Automatic_Client_Reconnect-C-code.pdf

Document information

More support for: WebSphere MQ
Capability

Software version: 7.0.1, 7.1, 7.5, 8.0

Operating system(s): AIX, HP-UX, Linux, Solaris, Windows

Reference #: 7017882

Modified date: 08 June 2010