Data flow from BPEL using BAM sensors to BAM data objects:

It seems that BPEL process sensor actions write messages containing selected data to a JMS topic or queue, and another process on BPEL side consumes these messages and invokes BAM web service for population BAM data objects.

What needs to be monitored and configured to make sure that data generated by BPEL sensor actions are not lost if corresponding BAM server is temporarily unavailable?

When the BAM Server is down, the corresponding data objects wont be available. During the design time what you do is to create a variable which contains the elements that you want to monitor in the BAM. In BAM u create data objects , then u map the schema from the BPEL to the BAM Data Objects ...You need a BAM Server connection which pulls up the metadata from the server ..If the BAM Server is down u wont get the BAM DOs...to keep a backup u can use DB as the sensor action so that the data from the sensor action is written to the DB. Using a DB Adapter I think the data from the Reports schema can be written to the Oracle BAM schema. So that even if the BAM Server is down the data is written to the Oracle BAM schema

If the BAM server is temporarily down, the BPEL server keeps trying to submit the data. You can actually see this behaviour in the BPEL domain logs.If the BPEL server is bounced before the BAM server comes back up, those pending transactions are lost -- i.e. they are not persisted permanently anywhere on the BPEL side.