The Cluster service and TCP/IP

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

The Cluster service and TCP/IP

The Cluster service requires the TCP/IP suite for its internal and client communication.

TCP/IP is an industry-standard suite of protocols, providing communication in a heterogeneous environment. Although TCP/IP is best known for its access to the Internet and Internet resources, TCP/IP is also well suited as an enterprise networking protocol because it provides interoperability between different types of computer systems. For more information on TCP/IP, see TCP/IP Core Networking Service.

The Cluster service and DHCP

The Windows ServerĀ 2003 family supports the use of DHCP addresses as public or private node addresses (you configure public and private node addresses through the Network Connections folder, not through cluster management software). The Cluster service uses the Plug and Play network support to handle the events that occur when a DHCP-allocated Internet protocol (IP) address changes. For more information about public and private networks, see Server cluster networks.

However, it is highly recommended that you use static IP addresses for each network adapter on each node. Using DHCP leases for node addresses has some disadvantages:

  • First, when the address lease expires for a network, the node cannot communicate over that network until it obtains a new address. This makes the node's availability dependent on the availability of the DHCP server; the node cannot communicate over the network until it obtains its address from the DHCP server.

  • Second, if an address lease expires on a network configured for public communication (communication between cluster nodes and clients), it might trigger failover for resource groups that used an IP Address resource on that network.

Caution

  • The Cluster service does not support the use of IP addresses assigned from a DHCP server for the cluster administration address (which is an IP address resource associated with the cluster name) or any other IP address resources. If possible, it is recommended that you use static IP addresses for all public and private node addresses.