Event ID 9 — Network Adapter Functionality

Applies To: Windows Server 2008

The network adapter to which Network Load Balancing (NLB) is bound must be properly configured and capable of performing NLB operations. If the adapter is not properly configured, the NLB driver may fail to bind to the adapter.

Event Details

Product: Windows Operating System
ID: 9
Source: Microsoft-Windows-NLB
Version: 6.0
Symbolic Name: MSG_ERROR_MEDIA
Message: NLB cluster [%2]: The NLB driver failed to bind to the adapter because the medium type is unsupported. Please confirm that you are trying to bind NLB to an Ethernet network adapter.


Ensure that NLB is bound to an Ethernet network adapter

For Network Load Balancing (NLB) to work, it must bind to an Ethernet network adapter.

Membership in the local Administrators group, or equivalent, is the minimum required to complete this procedure.

To check that NLB is bound to an Ethernet network adapter:

  1. Open Network and Sharing Center, and then click Manage network connections.
  2. Right-click the network adapter, and click Properties. Verify that the adapter is an Ethernet network adapter.



When you are using nlb.exe, you must be a member of the Administrators group on the host that you are configuring, or you must have been delegated the appropriate authority. If you are configuring a cluster or host by running nlb.exe from a computer that is not part of the cluster, you do not have to be a member of the Administrators group on that computer.

To verify that the network adapters are properly configured:

  1. Open an elevated Command Prompt window. Click Start, point to All Programs, click Accessories, right-click Command Prompt, and then click Run as administrator.
  2. Type nlb.exe query, which displays the current cluster state and the list of host priorities for the current members of the cluster.
  3. Type nlb.exe display, which displays details on the current cluster configuration and the IP configuration on the host operating system and the network adapter. Verify the configuration of the network adapter.


Network Adapter Functionality

NLB Cluster