paraDisE beyond the eArTH: Best Practice: SharePoint 2010 - Take advantage of using Network Load Balancing (NLB)

Enhance performance of the application tier (WFE) servers by fine tuning NLB

You can specify that a filtering mode apply to a numerical range of ports. You do this by defining a port rule with a set of configuration parameters that define the filtering mode. Each rule consists of the following configuration parameters:

The virtual IP address that the rule should be applied.

The TCP or UDP port range for which this rule should be applied.

The protocols for which this rule should apply, including TCP, UDP, or both.

The filtering mode that specifies how the cluster handles traffic described by the port range and protocols. In addition, you can select one of three options for client affinity: None, Single, and Class C. Single and Class C are used to ensure that all network traffic from a particular client be directed to the same cluster host. In order to allow Network Load Balancing to properly handle IP fragments, you should avoid using None when selecting UDP or Both for your protocol setting. Also the rules entered on each host in the cluster must have matching cluster IP addresses, port ranges, protocol types, and filtering modes.

Reference: http://technet.microsoft.com/en-us/library/cc778263(v=ws.10).aspx

Network Load Balancing references the dedicated IP address only when a single network adapter is used to handle both client-to-cluster traffic and other network traffic that must go specifically to the dedicated IP address. Network Load Balancing ensures that all traffic to the dedicated IP address is unaffected by the Network Load Balancing current configuration, including:

When this host is running as part of the cluster

When Network Load Balancing is disabled due to parameter errors in the registry

Typically, both the dedicated IP address and the cluster IP address, entered during setup in the Network Load Balancing Properties dialog box, must also be entered in the Internet Protocol (TCP/IP) Properties dialog box. Make sure that the addresses are the same in both places (in fact cluster ip address is automatically added to all cluster servers at the time of NLB convergence)

Reference: http://technet.microsoft.com/en-us/library/cc778263(v=ws.10).aspx

Multicast support is not enabled by default. To enable it, see Enable multicast support. However, if you do not enable multicast support, you are advised to consider using at least two network adapters (with one network adapter dedicated to handling client-to-cluster traffic) in order to achieve optimum performance and the full range of networking functionality. For more information, see Multiple network adapters and Optimizing network performance

Reference: http://technet.microsoft.com/en-us/library/cc778263(v=ws.10).aspx

following article specifies the IIS response to Load-Balanced Application Pool Behaviours

http://technet.microsoft.com/en-us/library/cc757659(v=WS.10).aspx

following article specifies the Best Practices used for configuring NLB.

http://technet.microsoft.com/en-us/library/cc740265(v=ws.10).aspx

Dedicate NLB Port Rules