Event ID 74 — NLB Host State Persistence

Applies To: Windows Server 2008

When configured to do so, the Network Load Balancing (NLB) host state will persist whenever the NLB cluster shuts down and restarts.

 

Event Details

Product: Windows Operating System
ID: 74
Source: Microsoft-Windows-NLB
Version: 6.0
Symbolic Name: MSG_WARN_HOST_STATE_UPDATE
Message: NLB cluster [%2]: NLB failed to update the NLB host state in the registry. This will affect the ability of NLB to persist the current state after the system restarts, if NLB has been configured to do so. To predict the state of NLB at the next restart, please delete the HKLM\SYSTEM\CurrentControlSet\Services\WLBS\Parameters\Interface\{GUID}\%3 registry value, which will cause the state at the next system restart to revert to the user-specified preferred initial host state.

Resolve

Confirm that the initial host state is correct

To check the initial Network Load Balancing (NLB) host state, you must first delete the registry key defined in the event log, and then confirm that the initial host state is correct.

Incorrectly editing the registry may severely damage your system. Before making changes to the registry, you should back up any valued data on your computer.

Delete the registry key defined in the event log entry

To delete the registry key defined in the event log entry:

  1. Open Registry Editor.
  2. To set the state of the NLB host at the next restart, delete the following registry key, if it exists: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\WLBS\Parameters\Interface\{GUID}\HostState. Deleting this key ensures that on the next restart, NLB will use the preferred initial host state.

The GUID is the globally unique identifier of the network adapter that is experiencing the problem. This will be the network adapter that is bound to NLB. If NLB is, or has been, bound to multiple network adapters, you can find the correct adapter by looking at the value for the ClusterIPAddress key for each GUID entry in the registry.

When you are using NLB Manager, 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 Manager 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.

Confirm that the NLB initial host state is correctly configured

To confirm the NLB initial host state is correctly configured:

  1. Click Start, click Administrative Tools, and then click Network Load Balancing Manager. You can also open NLB Manager by typing Nlbmgr at a command prompt.
  2. If NLB Manager does not already list the cluster, connect to the cluster.
  3. Right-click the host that you want to configure, and then click Host Properties.
  4. Click the Host Parameters tab, and then verify that the value in Initial host state is correct.

 

Verify

To ensure that the Network Load Balancing (NLB) host is functioning properly, you should check that the host state persists across cluster shutdowns and restarts.

When you are using NLB Manager, 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 Manager 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 check that the NLB host state persists across cluster shutdowns and restarts, after the cluster restarts, perform the following procedure.

  1. Click Start, click Administrative Tools, and then click Network Load Balancing Manager. You can also open NLB Manager by typing Nlbmgr at a command prompt.
  2. If NLB Manager does not already list the cluster, connect to the cluster.
  3. Right-click the host that you want to configure, and then click Host Properties.
  4. Click the Host Parameters tab, and then verify that the value in Initial host state is correct.

 

NLB Host State Persistence

NLB Cluster