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I am trying to test the limit of a Windows Server 2008 (64 bit with 15 GB RAM) machine for maximum inbound TCP/IP connections on a port. I am using C# with async sockets.

The issue I am facing is that server stops accepting more after 90-100K TCP connections even though of resources are still free (CPU, memory). There is no fixed limit after which is stops but it is in range of 90-100K and sometime even little more than that.

Does anyone have idea about this issue?

How many maximum TCP connections ever achieved on windows machine?

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TCP only has 65k ports available. If you use all those up, the server can't accept more connections.

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I am using only one port on sever. Therefore this shouldn't be any issue. My question is around total connections not ports. I already achieved 90K+ connection on the machine. – Ramesh Soni Jun 25 '12 at 9:10
The machine which you are running can to use dynamic ports outbound. You might be a better answer on Stack Overflow. – mrdenny Jul 1 '12 at 13:20

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