Symptoms: The IIS application throws a 503 error, but the application pool is still running. The CPU of the application is around 0.23 percent and the memroy is 4G. It seems that the application The application does not process any Http request. It lasted up to one hour util we terminate the process and restart it.
Environment: Windows Server 2008 R2
IIS 7.0
.Net Framework 3.5
Another point, our application uses session state server, and state server throws an exception "The state server has closed an expired TCP / IP connection. The IP address of the client is 127.0.0.1. The expired Read operation began at 08/30 / 2013 10:02:00." However there is no other evidence in the Event Viewer of Web Server and Application.
What happened? Does the application hang?
William