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File locking in MQ multi-instance queue managers

White paper


The objective of this document is to analyze the file locking activity in an MQ 8.0 multi-instance queue manager in Linux for the following files of the queue manager: master, active and standby.
These files help to coordinate when the Standby instance can become an Active instance.


There are only two scenarios that are traced:
- The startup trace is captured for both the Active and the Standby instance, and
- The graceful switchover from the Active to the Standby.

This document does not cover the trace of "failure" scenarios.
The queue manager in question is the only one active in both hosts for this scenario, in that way, there is no "contamination" in the traces from other queue managers.
The file system is NFS Version 4.

+ PDF File: File locking in MQ multi-instance queue managers.pdf

File locking in MQ multi-instance queue managers.pdf

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Document information

More support for: WebSphere MQ

Software version: 7.5, 8.0, 9.0

Operating system(s): Linux

Reference #: 7049989

Modified date: 16 May 2018

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