If you are using SQL Server or Analysis Services: I suggest you double check that your SNP settings, especially TCP Chimney Offset, are all OFF unless your NIC vendor has verified they support it and you have installed their version of drivers that support it. Windows 2003 SP2 turned it on by default, you can disable it with a hotfix (which updates three registry key values) or manually set the registry key values yourself. If the NIC vendor does support the settings they can improve your network performance, but when they don’t support it you can see odd connectivity problems.
My suggestion for a standard:
SNP/TCP Chimney settings will be disabled to avoid known problems with SQL Server and other products.
REASON: Performance and usability. When TCP Chimney is enabled it will often result in failed connectivity to SQL Server and/or dropped packets and connections that affect SQL server. See 948496 An update to turn off default SNP features is available for Windows Server 2003-based and Small Business Server 2003-based computers http://support.microsoft.com/default.aspx?scid=kb;EN-US;948496 and 942861 Error message when an application connects to SQL Server on a server that is running Windows Server 2003: “General Network error,” “Communication link failure,” or “A transport-level error” http://support.microsoft.com/default.aspx?scid=kb;EN-US;942861
948496 An update to turn off default SNP features is available for Windows Server 2003-based and Small Business Server 2003-based computers http://support.microsoft.com/default.aspx?scid=kb;EN-US;948496
Some of the known SNP/Chimney issues:
· 951037 Information about the TCP Chimney Offload, Receive Side Scaling, and Network Direct Memory Access features in Windows Server 2008 http://support.microsoft.com/default.aspx?scid=kb;EN-US;951037
· 942861 Error message when an application connects to SQL Server on a server that is running Windows Server 2003: “General Network error,” “Communication link failure,” or “A transport-level error” http://support.microsoft.com/default.aspx?scid=kb;EN-US;942861
· 945977 Some problems occur after installing Windows Server 2003 SP2 http://support.microsoft.com/default.aspx?scid=kb;EN-US;945977
· 947775 On a Windows Server 2003 computer that has a TCP Chimney Offload network adapter, TCP data stream may be corrupted when the network adapter indicates a MDL chain whose starting MDL has a nonzero offset http://support.microsoft.com/default.aspx?scid=kb;EN-US;947775
· 936594 You may experience network-related problems after you install Windows Server 2003 SP2 or the Scalable Networking Pack on a Windows Server 2003-based computer http://support.microsoft.com/default.aspx?scid=kb;EN-US;936594
· 947773 A Windows Server 2003-based computer responds slowly to RDP connections or to SMB connections that are made from a Windows Vista-based computer http://support.microsoft.com/default.aspx?scid=kb;EN-US;947773
· 946056 A Windows Server 2003-based computer responds slowly to RDP connections or to SMB connections that are made from a Windows Vista-based computer http://support.microsoft.com/default.aspx?scid=kb;EN-US;946056
· 940202 A Windows Server 2003-based computer may stop responding during shutdown after you install the Scalable Networking Pack http://support.microsoft.com/default.aspx?scid=kb;EN-US;940202
· 924325 Network applications that use the NetBT keep-alive transmissions may not work correctly after you install the Windows Server 2003 Scalable Networking Pack on a Windows Server 2003-based computer http://support.microsoft.com/default.aspx?scid=kb;EN-US;924325
· 945466 Stop error occurs when a computer that is TCP Offload Engine (TOE) enabled is running under stress with a “low resource simulation” mode http://support.microsoft.com/default.aspx?scid=kb;EN-US;945466
927168 TCP traffic stops after you enable both receive-side scaling and Internet Connection Sharing in Windows Vista or in Windows Server 2003 with Service Pack 1 or Service Pack 2 http://support.microsoft.com/default.aspx?scid=kb;EN-US;927168