Network Deployment (Distributed operating systems), v8.0 > Migration and coexistence > Migrate Messaging resources > Migrate from WAS v5 embedded messaging > Migrate v5.1 messages using the message migration utility
Run the message migration utility
The WAS message migration utility uses an XA (globally coordinated) transaction to migrate messages from the V5 embedded messaging provider on a WAS v5.1 application server to the default messaging provider (service integration) on an application server at a later version of the product.
- Ensure that we have a WAS v5.1 system that contains an embedded messaging server.
You do not have to start the v5.1 server.
- Ensure that no applications are reading from the WAS v5.1 queue manager when you run the message migration utility.
- Ensure that we have not modified or deleted the message queues on the v5.1 application server.
- Ensure that the version you are migrating to is a running system that fulfills the following conditions.
- The system is on the same host as the WAS v5.1 system.
- The system contains a messaging engine on the bus to which the messages will migrate (this is automatically included for you if you upgrade your server from v5.1 to a later version).
These conditions are met if you run the message migration utility at the correct point in the WAS migration sequence. The correct point is after we have run the WASPostUpgrade command and restarted the node on the version you migrate to.
You run the message migration utility only once for a particular queue, unless a failure occurs.
If a failure occurs during message migration, it is safe to run the message migration utility again in the same direction because messages are moved rather than copied. Whether you successfully try a failing message migration again, or delete the message, the message ordering of the remaining messages is preserved on the queue on the current version of the product.
During successful migration, messages are moved from the WAS v5.1 system to the later system. No copy is left on the v5.1 server queue.
For more information about the XA transaction, see XA recovery.
Procedure
- Follow the actions indicated by the message migration utility.
- In the "Select the direction of migration" panel, select Migrate messages from v5 to later_version.
- Select a message reliability to apply to messages that are to be migrated. More details on the choice of reliability levels can be found in the Message Reliability Levels topic.
- We can migrate multiple queues during a single run of the utility.
Results
- If the first message migration attempt fails, run the migration utility again.
- If a queue has a failing message, complete one of the following operations:
- Try the failing message again, in case there is a transient error.
- Delete the failing message and go on to the next message.
- Stop the queue that has the failing message and move on to the next queue.
What to do next
For information about the reversal of message migration, see Reversing the migration of messages by using the message migration utility.