Note Support for fault-tolerant technology is the responsibility of the hardware manufacturer. (Fault-tolerant technology includes the hardware and the drivers.)
Note If you use Application Center 2000 to configure NLB, it will set NLB to unicast mode.
If you use NLB in unicast mode, you may have to manually set the card's Locally Administered address (LAA) to the NLB cluster unicast MAC address. To do this, you must configure the driver software for the load balanced adapter on each computer in the cluster. Do not set the LAA for NLB clusters that operate in multicast mode.
Important If you manually set the unicast LAA, you must also manually remove the unicast LAA when you remove the server from the cluster. If you do not remove the unicast LAA when the server is removed from the cluster, you may receive MAC address conflicts.
This difficulty occurs only on the NLB interface and does not affect teamed, non-clustered interfaces on the same server. Many hardware manufacturers have updated drivers to correct this problem. Also, when you use multicast instead of unicast for NLB, NLB can function in a network adapter teaming environment because NLB does not overwrite the physical media access control address. From the perspective of Microsoft Product Support Services (PSS), use of teaming on clustered or dedicated interfaces is acceptable. However, if problems that occur seem to be related to teaming, PSS may require that you disable teaming while the problem is investigated. If this disabling of teaming itself resolves the problem, you must seek assistance from the hardware manufacturer.
Article ID: 278431 - Last Review: May 25, 2010 - Revision: 1