Thursday, 21 August 2008

Windows 2008 and Terminal Server Stream Disconnected

Problem: DELL Server with Broadcom NetXtreme Gigabit Ethernet card server running Windows 2008. If you connect to server via RDP, you loose the connection with an error unexpectedly. You will see something like this on client side:

The terminal Server has ended the connection.

On the server you will see something like this:


As mentioned in event log there is a problem with RDP security layer. There is a very nice support article as well on Microsoft. Please have a look at following link:

Nice, simple and easy Happy Working but there is one problem!!! This article is the most closet article you can find for the problem description and it does not solve your problem.

I have dumped the RDP packets with Netmon 3.1 and I do not see any session termination from the server side. After doing lot of research (and to save that lot of time of yours), I found the problem with Broadcom NetXtreme Gigabit Ethernet adapter.

By default in our kick on Windows 2008, we have enabled advanced features such as IPv4 Checksum Offload, IPv4 Large Send Offload (LSO) and Receive Side Scaling (RSS). I strongly recommend you to visit following link for more information:

Large Send Offloading divides the packet into small chunks and creation of TCP packet happens on the network card. It turned out that issue is due to LSO feature enabled and TS session service detected a problem with data stream. In order to stabilize the RDP session, we need to disable the LSO offloading from Broadcom Advanced Control Suite as follow:

Uday Pandya

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