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Deploying Microsoft SQL Server 2008 based Decision Support Systems using Dell EqualLogic 10GbE iSCSI Storage 15

To configure OS TCP offload:

C:\>netsh int tcp set global chimney=enabled

To verify OS TCP offload:

C:\>netsh int tcp show global

DisableNICTeamingandUnusedNICs

Since we enabled MPIO in our test configurations, we disabled NIC teaming on all ports used for iSCSI

connections

. We also disabled any unused NIC ports on the system to simplify system management

and reduce the chances of making errors during configuration.

It is a best practice to disable NIC teaming on all ports used for iSCSI connections. You should also

disable unused NIC ports to simplify system management and reduce the chance for configuration

errors.

4.4.3 OptimizeMPIOConfigurationWithEqualLogicDSM

In both test configurations we enabled the Dell EqualLogic Device Specific Module (DSM) for Multi-

Path I/O (MPIO). The DSM is provided by the Dell EqualLogic Host Integration Toolkit (“HIT Kit”) for the

server operating system. The HIT Kit can be obtained from Dell EqualLogic support. Figure 6 shows the

MPIO configuration for a volume hosted on 3 arrays. We used the default value (2) for the number of

connections per member. This created a total of 6 connections to the volume since the volume spans

three pool members. Only logical connections to the active storage controller are shown in Figure 6.

See Microsoft iSCSI Initiator Version 2.x Users Guide:

http://download.microsoft.com/download/a/e/9/ae91dea1-66d9-417c-ade4-

92d824b871af/uguide.doc

Note: More information on enabling TCP offload in the operating system can be found in

the following Microsoft Knowledgebase Articles:

 Information about the TCP Chimney Offload, Receive Side Scaling, and Network

Direct Memory Access features in Windows Server 2008:

http://support.microsoft.com/kb/951037

 The Microsoft Windows Server 2003 Scalable Networking Pack release:

http://support.microsoft.com/kb/912222

As an alternative to ToE mode, the network card can also be setup in the iSCSI Offload

Engine (iSOE) mode. The EqualLogic MPIO DSM is designed to work with ports operating in

iSOE mode too. We did not validate iSOE mode in our test configuration.