Disable New Network Load Balancing Traffic Handling for Specific Ports

Applies To: Windows Server 2008, Windows Server 2008 R2

The procedures below describe how to disable new Network Load Balancing (NLB) traffic handling for specified ports.

Disabling new Network Load Balancing traffic handling for specific ports

To open NLB Manager, 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.
If NLB Manager does not already list the cluster, connect to the cluster.
Right-click a host or a cluster, and then click Control Ports.
To disable new traffic handling, click Drain.

To disable new traffic handling and stop Network Load Balancing, click Drainstop.

When you are using Network Load Balancing (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.
This procedure has no effect if the specified hosts have not started cluster operations.
Drain disables new traffic handling for the rule that contains the specified port in the port range. New connections to the specified hosts are not allowed but all active connections are maintained. To disable active connections, use the Disable command instead.
Performing the drain command at the cluster level drains the specified ports on all hosts within the cluster. Performing the drain command at the host level drains the ports on the specific host only.

To open a Command Prompt window, click Start, right-click Command Prompt, and then click Open.
Type one of the following commands:
- To disable traffic handling for specific ports, type:
```
nlb.exe drain vip[:port|:all] | all[:port|:all] cluster[:host]| all [local|global]
```
- To disable new traffic handling and stop Network Load Balancing, type:
```
nlb.exe drainstop
```

When you are using Network Load Balancing (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.
This command has no effect if the specified hosts have not started cluster operations.
Drain disables new traffic handling for the rule that contains the specified port in the port range. New connections to the specified hosts are not allowed, but all active connections are maintained. To disable active connections, use the Disable command instead.
Performing the drain command at the cluster level drains the specified ports on all hosts within the cluster. Performing the drain command at the host level drains the ports on the specific host only.