Disable and block all Network Load Balancing traffic handling for specific ports

Article
10/08/2009

Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1, Windows Server 2003 with SP2

To disable and block all Network Load Balancing traffic handling for specific ports

Using the Windows interface
Using a command line

Using the Windows interface

Open Network Load Balancing Manager.
If Network Load Balancing Manager does not already list the cluster, connect to the cluster.
Right-click a host or a cluster, and then click Control Ports.
Select the port rule that contains the ports that you want to disable and then click Disable.

Important

To start Network Load Balancing Manager, open a Command prompt. From the command window, type NLBMgr, and then press ENTER.

Notes

When using Network Load Balancing 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. As a security best practice, consider using Run as to perform this procedure. If you are configuring a cluster or host by running Network Load Balancing Manager from a computer that is not part of the cluster, you do not need to be a member of the Administrators group on that computer. For more information, see Default local groups, Default groups, and Using Run as.
To start Network Load Balancing Manager, open a Command prompt. From the command window, type NLBMgr, and then press ENTER.
This command disables and immediately blocks all traffic handling for the rule whose port range contains the specified port. All ports specified by the port rule are affected.
All active connections on the specified hosts are blocked. To maintain active connections, use the drain function instead.
This has no effect if the specified hosts have not started cluster operations.
For information on how to enable specific ports, see "Enable Network Load Balancing traffic handling for specific ports" in Related Topics.

Using a command line

Open Command Prompt.
Type:

nlb.exe disablevip[:port|:all] | all[:port|:all] cluster[:host]| all [local|global]

For more information about the parameters that you can use with this command, see "Nlb" in Related Topics.

Notes

To run nlb.exe from a remote computer, you must enable remote control on the host that is running Network Load Balancing. The Network Load Balancing remote control option presents many security risks, including the possibility of data tampering, denial of service and information disclosure. Only use remote control on a secure computer within your firewall. Because of the many security risks remote control presents, it is recommended that you do not enable the remote control feature. Instead, use other remote management tools such as Network Load Balancing Manager or Windows Management Instrumentation (WMI).
To open a command prompt, click Start, point to All programs, point to Accessories, and then click Command prompt.
To run nlb.exe from a remote computer, you must enable remote control on the host that is running Network Load Balancing. The Network Load Balancing remote control option presents many security risks, including the possibility of data tampering, denial of service and information disclosure. Only use remote control on a secure computer within your firewall. Because of the many security risks remote control presents, it is recommended that you do not enable the remote control feature. Instead, use other remote management tools such as Network Load Balancing Manager or Windows Management Instrumentation (WMI).
This command disables and immediately blocks all traffic handling for the rule whose port range contains the specified port. All ports specified by the port rule are affected.
All active connections on the specified hosts are blocked. To maintain active connections, use the drain function instead.
This has no effect if the specified hosts have not started cluster operations.
For information on how to enable specific ports, see "Enable Network Load Balancing traffic handling for specific ports" in Related Topics.

Information about functional differences

Your server might function differently based on the version and edition of the operating system that is installed, your account permissions, and your menu settings. For more information, see Viewing Help on the Web.

Disable and block all Network Load Balancing traffic handling for specific ports

To disable and block all Network Load Balancing traffic handling for specific ports

Using the Windows interface

Using a command line

Information about functional differences

See Also

Concepts

Additional resources