Enable a network for cluster use

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

To enable a network for cluster use

  1. Open Cluster Administrator.

  2. In the console tree, double-click to expand Cluster Configuration, and then click Networks.

  3. In the details pane, click the network you want to enable.

  4. On the File menu, click Properties.

  5. Select the Enable this network for cluster use check box.

  6. Specify how you want the network to be used by the cluster:

    • To use the network for communications with clients and between nodes, click All communications (mixed network).

    • To use the network only for communications between nodes, click Internal cluster communications only (private network).

    • To use the network only for communications with clients, click Client access only (public network).


  • To perform this procedure, you must be a member of the Administrators group on the local computer, or you must have been delegated the appropriate authority. If the computer is joined to a domain, members of the Domain Admins group might be able to perform this procedure. As a security best practice, consider using Run as to perform this procedure.

  • To open Cluster Administrator, click Start, click Control Panel, double-click Administrative Tools, and then double-click Cluster Administrator.

  • If multiple network interfaces exist on the same subnet, only the first one can be used. Others will be ignored by the Cluster service.

  • With Windows ServerĀ 2003 with Service PackĀ 1, if you use Windows Firewall, use the Security Configuration Wizard to configure it. For more information, see "Using Windows Firewall with a Server Cluster" in Related Links.

  • If you are protecting your network with a firewall other than Windows Firewall, take note of the following list of ports needed by server clusters:

    • 135 (RPC endpoint mapper/DCOM).

    • 135 (RPC endpoint mapper over UDP).

    • 3343 (used by the Cluster Network Driver).

    • 445 (SMB).

    • 139 (NetBIOS session service).

    • For cluster nodes running many services, ports 5000-5099 (or more) might need to be open for remote RPC connectivity to Cluster Administrator. When these ports are closed, event log error 1721 might occur when you connect to a cluster through Cluster Administrator (unless you just type a period in Cluster Administrator).

      This problem can occur because the Cluster service requires at least 100 ports for communication through remote procedure calls (RPC). The number of ports available to the Cluster service can become too small when other services are using some of the necessary ports. Such services include Windows DNS service, Windows Internet Name Service (WINS), the Microsoft SQL Server service, and others.

    • If the nodes are separated by a firewall, ports 8011-8031 must be open for internode RPC connectivity. Otherwise, errors in the cluster log will indicate that a "Sponsor" is not available. These errors occur because there are not enough ports available for RPC communication between a node that is trying to join the cluster and a node that can "sponsor" that node.

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.

See Also


Disable a network for cluster use
Change how the cluster uses a network
Server cluster networks
Network Configuration in a Server Cluster
Setting network properties
Using Windows Firewall with a server cluster