National Protection and Programs, Directorate for Science and Technology, Office of Health Affairs, the Transport [EOF]
FR runs on nginx 1.2.4, which is not the latest. If you look into the CHANGES you will see more worker thread crashes fixed in 1.3 than one could imagine. That's probably what happens here - a thread is spawned to handle the connection; the thread dies at some point and the resources - including the accepted socket connection - are freed. The HTTP agent gets FIN.