Cluster Networking Requirements

Applies To: Windows Server 2003 with SP1

This section describes the requirements that Server cluster puts on the network infrastructure. These requirements must be met for the Server cluster solution to function correctly.

General Requirements

This section describes the requirements for any Server cluster deployment.

  • The complete hardware configuration for a cluster must be selected from the Cluster Hardware Compatibility List (HCL). The network interface controllers along with any other components used in certified cluster configurations must have the Windows logo and appear on the Microsoft Hardware Compatibility List.

    (Windows 2000, Windows Server 2003)

Note

A cluster built from logged components that do not appear on the cluster HCL is NOT a qualified configuration.

  • Two or more independent networks must connect the nodes of a cluster in order to avoid a single point of failure. The use of two local area networks (LANs) is required; cluster configurations using a single network are not being supported.

    (Windows 2000, Windows Server 2003)

  • Each cluster network must fail independently of all other cluster networks. That is, two cluster networks must not have a component in common that can cause both to fail simultaneously. For example, the use of a multi-port network interface controller to attach a node to two cluster networks would not meet this requirement in most cases because the ports are not independent. Likewise, two networks that share a switch could also have a single point of failure. The simplest way to ensure that your cluster meets this requirement is to use physically independent components to construct cluster networks.

    (Windows 2000, Windows Server 2003)

  • All of the adapters used to attach nodes to the same cluster network must use the same communication settings – e.g. the same Speed, Duplex Mode, Flow Control, and Media Type. If the adapters are connected to a switch, the port settings of the switch must match those of the adapters.

    (Windows 2000, Windows Server 2003)

  • Each cluster network must be configured as a single IP subnet whose subnet number is distinct from those of other cluster networks. For example, a cluster could use two networks configured with the following subnet addresses: 10.1.x.x and 10.2.x.x with mask 255.255.0.0. Addresses may be assigned to the nodes dynamically by DHCP, but manual configuration with static addresses is recommended (see section Cluster Networking Best Practices). The use of Automatic Private IP Addressing (APIPA) to configure cluster networks is not supported. Also APIPA is not designed for use with computers that are attached to multiple networks.

    (Windows 2000, Windows Server 2003)

  • At least two of the cluster networks must be configured to support internal communication between cluster nodes in order to avoid a single point of failure. That is, the roles of these networks must be configured as either Internal Cluster Communications Only or All Communications in Cluster Service. Typically, one of these networks is a private interconnect dedicated to internal cluster communication (see section Cluster Networking Best Practices).

    (Windows 2000, Windows Server 2003)

  • The use of network interface controller teaming on all cluster networks concurrently is not supported. At least one of the cluster networks that are enabled for internal communication between cluster nodes must not be teamed. Typically, the unteamed network is a private interconnect dedicated to this type of communication. The use of network interface controller teaming on other cluster networks is acceptable; however, if communication problems occur on a teamed network, Microsoft Product Support Services may require that teaming be disabled. If this action resolves the problem or issue, then you must seek further assistance from the manufacturer of the teaming solution.

    (Windows 2000, Windows Server 2003)

  • The nodes of a cluster must belong to a single domain. The domain configuration must meet the following requirements in order to avoid a single point of failure in the authentication process:

    • The domain must have at least two domain controllers,

    • If DNS is used to resolve names in the domain, then at least two DNS servers must be deployed as well. The DNS servers should support dynamic updates,

    • Each domain controller and cluster node must be configured with a primary and at least one secondary DNS server. If the domain controllers are also DNS servers, then each should point to itself for primary DNS resolution and to the other DNS servers for secondary resolution,

    • At least two domain controllers must be configured to be Global Catalog Servers.

    (Windows 2000, Windows Server 2003)

Geographically Dispersed Clusters

This section describes the additional requirements that geographically dispersed clusters have:

  • The nodes in a cluster may be on different physical networks; however, the private and public network connections between cluster nodes must appear as a single, non-routed LAN using technologies such as virtual LANs (VLANs).

    (Windows 2000, Windows Server 2003)

  • The round-trip communication latency between any pair of cluster nodes must be no more than 500 milliseconds.

    (Windows 2000, Windows Server 2003)

  • As with LANs, each VLAN must fail independently of all other cluster networks.

    (Windows 2000, Windows Server 2003)

  • Due to the complexity of geographically dispersed clusters, you need to involve the hardware manufacturer or hardware vendor in any issue. Often, there is third-party software and drivers that are required for the clusters to function. Microsoft Product Support Services may not be aware of how these components interact with Windows Clustering.

    (Windows 2000, Windows Server 2003)