New Dell PowerEdge R910, 4x8 Intel X7560, 192GB RAM, hardware NUMA, local RAID, Broadcom NetExtreme II multiport NIC, unteamed, TCP Offload disabled, RSS disabled, NetDMA disabled, Hyperthreading disabled.

SQL Server 2005 SE x64 SP3 on Windows Server 2008 R2 EE x64. No other apps on server. Max Mem = 180GB, Max DOP = 4.

Existing Windows Server 2003 R2 EE x64 app server connecting to Dell via firewall using SQL Authenticated logins.

Symptoms: Intermittent errors at the app server:

A transport-level error has occurred when sending the request to the server. (provider: TCP Provider, error: 0 - An existing connection was forcibly closed by the remote host.)

Findings: Running queries from SSMS located on another machine within the same domain as the SQL Server run without error. SQLIO showed good performance. Windows and SQL logs show no related messages. Microsoft reveiwed PssDiag trace and stated that "We are not seeing timeouts from SQL Side. The queries bring run against the database are timing out within 9secs. This is a database connectivity error." "we can also see from the AttnSeq column that we are also not seeing any Attentions from the SQL Side.". Dell has confirmed that we are using the latest Broadcom drivers.