Migrating from earlier unsupported releases of MQSeries

For production systems, the recommended migration path from an unsupported release of MQSeries(R) is first to migrate to WebSphere MQ Version 5.3.1, following the instructions given in the documentation for that release, and then to migrate to Version 6.0 following the instructions in this chapter. Ensure that your system is stable at Version 5.3.1 before migrating to Version 6.0, so that you have a system to revert to should you need to. Details about reversion are given in this chapter:

For a test system, it might be appropriate to migrate straight to WebSphere MQ Version 6.0. The additional steps that must be considered when migrating from unsupported releases of MQSeries are discussed in Appendix A. Migrating from an unsupported release of MQSeries:

After you have migrated to WebSphere MQ Version 6.0 using this method, it will not be possible to revert to the previous version. You should take complete backups of your system to ensure you can restart from backups if you need to use the old release again.

When WebSphere MQ page sets and log data sets have been used by a queue manager running at Version 6.0, the effect of trying to use those data sets with a queue manager which has been reverted to use Version 5.2 or earlier is undefined and unpredictable and can lead to data loss, loops or system outage.

You can restart a queue manager running at Version 5.2 or earlier using the full set of backups taken before migration. Any changes made to the system after the backups were taken or while running at Version 6.0 will be lost.