Question On JMS

[Nandu itha]

Question Duplicate Consumption of messages in Clustered Envirornment with Publish/Subscriber type

Lets i have a MDB and that got deployed in clustered envirornment .

One of the client sent a message to the topic and the consumer or subscriber to this topic have been deployed in the clustered envirornment and is there a guarantee like when this topic is consumed by 1 MDB in one of the container and will the same topic will be consumed by the same MDB in another container?

If its consumed second container its like duplicate consumption will it really happen or am i thinking too much .

If this can happen how should we avoid this.

Thanks
-Nandu

[Ionut Bucurescu]

The message will be consumed only once by the same subscriber inside the cluster otherwise it breaks the JMS spec. The topic is visible to the entire cluster.