If you are migrating a high-availability domain, special considerations might apply.
High availability is the requirement for a system to be running all, or for a very high proportion of, the time. Providing a high-availability environment involves having multiple brokers so that some brokers can be used for backup purposes. The entire production domain might be duplicated so that the backup system can be switched on in the event of a problem.
When you migrate, a high-availability environment presents a potential problem because a vulnerable period exists between stopping the previous version of the product, and installing and starting WebSphere Message Broker Version 6.1. One solution is to install and configure WebSphere Message Broker Version 6.1 while the previous version of the product is running in parallel, and then switch to WebSphere Message Broker Version 6.1. Install WebSphere Message Broker Version 6.1 on the same computers that are running the previous version of the product, or on a different set of computers.
The following sections of this topic provide a general framework for how you might want to migrate your high-availability domain. You might need to adjust these instructions to suit your specific circumstances. Refer to the product-specific migration topics for detailed migration instructions.
When you are ready to perform migration, back up your resources.