Error retrieving connections in jboss to multiple databases even though there is no transaction

Question

We are in the process of upgrading from JBoss 6 to JBoss 7. The nature of our application has a separate database instance per customer, as well as a core configuration data

Answer 1

OK, it turns out that unlike JBoss6, a NOT_SUPPORTED transaction is still a transaction as far as the validation logic for retrieving data sources is concerned.

The way to work around this is to make the whole EJB a bean managed transaction:

@TransactionManagement(TransactionManagementType.BEAN)

This unfortunately limits some flexibility in that some times you would rather control this method-by-method, but it isn't too painful a workaround.