Resolution:
In dual server mode, the BusinessConnect DMZ and Interior server communicate with each other via a handshake mechanism.  When the DMZ picks up a file via the inbound file poller or receives an inbound http/s/ca request, it immediately sends an RV message to the interior server on the &ltsubject prefix>.&ltinstallation name>.DMZMSH-MESSAGE subject.  After the interior server receives and processes the message, it sends a response back to the DMZ, which either completes the appropriate file disposition with the file poller, or sends an http/s/ca response.  The DMZ then sends an confirmation to the interior server to complete the handshake process.

The DMZ waits for a response from the interior server based on a timeout set under the Intercomponent Advanced tab of the BusinessConnect application configuration.  The parameter is called "DMZ Interior Timeout (seconds)" and by default it is set to one hour (3600 seconds).  The "Activity Timed Out" message appears in the log when the DMZ does not get a response from the interior server within the timeout period.

These timeouts can be caused by:

1.  Excessive processing time by the interior server.  This is true with large EDI interchange files (especially with HIPAA interchanges).

2.  Excessive delay by the BW private process in returning a RESPONDER.RESPONSE to BC after a RESPONDER.REQUEST is sent (for synchronous transaction only).

3.  An exception being thrown in the interior server, which interrupts the processing of a transaction.

4.  Bad RV communication between the DMZ server and the interior server, usually due to RVRD issues.

To troubleshoot these activity time out errors:

1.  Check the audit log for any transaction initiated one hour (or the DMZ timeout value) earlier than the Activity Timed Out timestamp in the BusinessConnectDMZServer.log file to see if there is a transaction that is taking a long time to process.  If you do see these errors, adjust the DMZ Interior Timeout accordingly.  

2.  For synchronous transactions, make sure that the private process is returning a message to BC.

3.  Check the interior server log for any Java stack traces related to an exception being thrown during job processing.

4.  Do a tibrvlisten on the interior server using the subject listed above, and make sure that you see DMZMSH-MESSAGE flowing on the interior server side.

I am seeing a number of "Activity timed out" messages in the BusinessConnectDMZServer.log file.What causes this?