For Forefront Threat Management Gateway, Medium Business Edition, the following event may be logged:
- For User Datagram Protocol (UDP) connections, if a client program reaches this connection limit, any additional UDP connections cause a previous UDP connection to be dropped.
- For Transmission Control Protocol (TCP) connections, if a client program reaches this connection limit, no additional connections are permitted.
If you run your ISA Server computers back-to-back to create a perimeter network, you are more likely to experience this behavior. The internal ISA Server computer translates all the internal clients by using the NAT protocol. The frames are sent to the external ISA Server computer, and this computer uses the NAT protocol to translate all the internal clients again. To the external ISA Server computer, all the connections look similar to one client. The connections use the perimeter network IP address of the internal ISA Server computer. Therefore, to the external ISA Server computer, 40 internal clients look similar to 1 client that has 40 different connections.
Article ID: 838706 - Last Review: Dec 10, 2008 - Revision: 1