Event ID 15 — NLB Dedicated IP (DIP) Addresses Functionality

Applies To: Windows Server 2008 R2

The dedicated IP addresses in Network Load Balancing (NLB) must be properly configured and be able to contact individual NLB cluster hosts. If the dedicated IP address is not configured correctly, you cannot use it to manage the host or for other non-cluster-related communication.

 

Event Details

Product: Windows Operating System
ID: 15
Source: Microsoft-Windows-NLB
Version: 6.1
Symbolic Name: MSG_WARN_DED_IP_ADDR
Message: NLB cluster [%2]: The dedicated IP (DIP) address %3 is invalid. The cluster will converge and operate normally without this DIP. However, if this DIP is required for remote cluster management, make sure that the DIP is specified in a valid IPv4 or IPv6 address format.

Resolve

Ensure that the dedicated IP address is in a valid format

If the dedicated IP address is not valid, the Network Load Balancing (NLB) cluster will converge and operate normally without the IP address. However, if the IP address is required for remote cluster management, make sure that the IP address is specified in a valid IPv4 or IPv6 address format.

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 ensure that the dedicated IP address is in a valid IPv4 or IPv6 format:

  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, in IP address, verify that the IPv4 or IPv6 address is correctly formatted. IPv4 addresses use the standard Internet dotted notation (for example, w.x.y.z). IPv6 addresses use 16-byte addresses, typically expressed in colon-hexadecimal notation. Colon-hexadecimal notation uses eight 4-digit hexadecimal numbers, with colons separating the 16-bit blocks (the 4-digit numbers). To manage addresses more easily, IPv6 suppresses leading zeros and compresses a single contiguous all-zero 16-bit block, represent the contiguous block with two colons (::). This is known as double-colon compression. An example of an IPv6 address with leading zeros suppressed is: FEC0:0:0:0:2AA:FF:FE3F:2A1C.

 

Verify

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 dedicated IP address can be reached:

  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 display,which displays extensive information about your current Network Load Balancing (NLB) parameters, cluster state, and past cluster activity. The registry information retrieved by the display command shows what the next state of NLB would be if a reload or some other operation that causes the driver to read the registry were to be performed.
  3. Type nlb.exe params, which displays information about your current NLB configuration, including the dedicated IP addresses used by the NLB driver.

 

NLB Dedicated IP (DIP) Addresses Functionality

NLB Cluster