Important Information to Review

Planning and Preparing for Cluster Installation

Beginning the Cluster Installation on the First Cluster Node

With Microsoft® Windows Server™ 2003, Enterprise Edition, and Microsoft Windows Server 2003, Datacenter Edition, you can use clustering to ensure that users have constant access to important server-based resources. With clustering, you create several cluster nodes that appear to users as one server. If one of the nodes in the cluster fails, another node begins to provide service (a process known as failover). Critical applications and resources remain continuously available.

For technical information and resources to help you evaluate, deploy, and administer the Windows server operating systems, see the Windows Server TechCenter on the Web at: http://go.microsoft.com/fwlink/?LinkId=28944

Microsoft supports only complete server cluster systems that are compatible with the Windows Server 2003 family. Confirm that your entire cluster solution is compatible with products in the Windows Server 2003 family by checking the hardware compatibility information in the Windows Catalog at: http://go.microsoft.com/fwlink/?LinkId=37824

For cluster disks, you must use the NTFS file system and configure the disks as basic disks. You cannot configure cluster disks as dynamic disks, and you cannot use features of dynamic disks such as spanned volumes (volume sets).

Review the manufacturer’s instructions carefully before you begin installing cluster hardware. Otherwise the cluster storage could be corrupted. If your cluster hardware includes a SCSI bus, be sure to carefully review any instructions about termination of the SCSI bus and configuration of SCSI IDs.

To simplify configuration and eliminate potential compatibility problems, consider using identical hardware for all nodes.

In your planning, decide what kind of communication each network adapter will carry. The following list provides details about the types of communication that an adapter can carry:

• Only node-to-node communication (private network). This implies that the server has one or more additional adapters to carry other communication.
  
  For node-to-node communication, you connect the network adapter to a private network that is used exclusively within the cluster. Note that if the private network uses a single hub or network switch, that piece of equipment becomes a potential point of failure in your cluster.
  
  The nodes of a cluster must be on the same subnet but you can use virtual LAN (VLAN) switches on the interconnects between two nodes. If you use a VLAN, the point-to-point, round-trip latency must be less than 1/2 second and the link between two nodes must appear as a single point-to-point connection from the perspective of the Windows operating system running on the nodes. To avoid single points of failure, use independent VLAN hardware for the different paths between the nodes.
  
  If your nodes use multiple private (node-to-node) networks, it is a best practice for the adapters for those networks to use static IP addresses instead of DHCP.
  
  
• Only client-to-cluster communication (public network). This implies that the server has one or more additional adapters to carry other communication.
  
  
• Both node-to-node and client-to-cluster communication (mixed network). When you have multiple network adapters per node, a network adapter that carries both kinds of communication can serve as a backup for other network adapters.
  
  
• Communication unrelated to the cluster. If a clustered node also provides services unrelated to the cluster, and there are enough adapters in the cluster node, you might want to use one adapter for carrying communication unrelated to the cluster.
  
  

The nodes of a cluster must be connected by two or more local area networks (LANs); at least two networks are required to prevent a single point of failure. A server cluster whose nodes are connected by only one network is not a supported configuration. The adapters, cables, hubs, and switches for each network must fail independently. This usually implies that the components of any two networks must be physically independent.

At least two networks must be configured to handle All communications (mixed network) or Internal cluster communications only (private network).

The recommended configuration for two adapters is to use one adapter for the private (node-to-node only) communication and the other adapter for mixed communication (node-to-node plus client-to-cluster communication). Do not use teaming network adapters on the private network.

If you use fault tolerant network adapters, create multiple private networks instead of a single fault-tolerant network.

Do not configure a default gateway or DNS or WINS server on the private network adapters. Do not configure private network adapters to use name resolution servers on the public network; otherwise a name resolution server on the public network might map a name to an IP address on the private network. If a client then received that IP address from the name resolution server, it might fail to reach the address because no route from the client to the private network address exists.

Configure WINS and/or DNS servers on the public network adapters. If Network Name resources are used on the public networks, set up the DNS servers to support dynamic updates; otherwise the Network Name resources may not fail over correctly. Also, configure a default gateway on the public network adapters. If there are multiple public networks in the cluster, configure a default gateway on only one of these.

When you use either the New Server Cluster Wizard or the Add Nodes Wizard to install clustering on a node that contains two network adapters, by default the wizard configures both of the network adapters for mixed network communications. As a best practice, reconfigure one adapter for private network communications only. For more information, see "Change how the cluster uses a network" in Help and Support Center for Windows Server 2003, Enterprise Edition. To open Help and Support Center, after completing Setup, click Start, and then click Help and Support.

Consider choosing a name for each connection that tells what it is intended for. The name will make it easier to identify the connection whenever you are configuring the server.

Manually configure the communication settings, such as Speed, Duplex Mode, Flow Control and Media Type of each cluster network adapter. Do not use automatic detection. You must configure all of the cluster network adapters to use the same communication settings.

The adapters on a given node must connect to networks in different subnets.

Do not use the same IP address for two network adapters, even if they are connected to two different networks.

Obtain a static IP address for the cluster itself. You cannot use DHCP for this address.

Determine how to handle the IP addressing for the individual cluster nodes. Each network adapter on each node requires IP addressing. It is a best practice to assign each network adapter a static IP address. As an alternative, you can provide IP addressing through DHCP. If you use static IP addresses, set the addresses for each linked pair of network adapters (linked node-to-node) to be on the same subnet.

Note that if you use DHCP for the individual cluster nodes, it can act as a single point of failure. That is, if you set up your cluster nodes so that they depend on a DHCP server for their IP addresses, temporary failure of the DHCP server can mean temporary unavailability of the cluster nodes. When deciding whether to use DHCP, evaluate ways to ensure availability of DHCP services, and consider the possibility of using long leases for the cluster nodes. This helps to ensure that they always have a valid IP address.

Determine or obtain an appropriate name for the cluster. This is the name administrators will use for connections to the cluster. (The actual applications running on the cluster typically have different network names.) The cluster name must be different from the domain name, from all computer names on the domain, and from other cluster names on the domain.

Make sure that the cluster nodes all have computer accounts in the same domain. Cluster nodes cannot be in a workgroup.

To install and configure the cluster service, you must be using an account that is in the local Administrators group on each node. As you install and configure each node, if you are not using an account in the local Administrators group, you will be prompted to provide the logon credentials for such an account.

Create or obtain the Cluster service user account. This is the name and password under which the Cluster service will run. You need to supply this user name and password during cluster installation.

It is best if the Cluster service user account is an account not used for any other purpose. If you have multiple clusters, set up a unique Cluster service user account for each cluster. The account must be a domain account; it cannot be a local account. However, do not make this account a domain administrator account because it does not need domain administrator user rights.

As part of the cluster setup process, the Cluster service user account is added to the local Administrators group on each node. As well as being a member of the local Administrators group, the Cluster service user account requires an additional set of user rights:

• Act as part of the operating system.
  
  
• Back up files and directories.
  
  
• Adjust memory quotas for a process.
  
  
• Increase scheduling priority.
  
  
• Log on as a service.
  
  
• Restore files and directories.
  
  

These user rights are also granted to the Cluster service user account as part of the cluster setup process. Be aware that the Cluster service user account will continue to have these user rights even after all nodes are evicted from the cluster. The risk that this presents is mitigated by the fact that these user rights are not granted domain wide, but rather only locally on each former node. However, remove this account from each evicted node if it is no longer needed.

Be sure to keep the password from expiring on the Cluster service user account (follow your organization’s policies for password renewal).

Plan on setting aside a volume on your cluster storage for holding important cluster configuration information. This information makes up the cluster quorum resource, which is needed when a cluster node stops functioning. The quorum resource provides node-independent storage of crucial data needed by the cluster. For important information on quorum resource options, see "Quorum Resource Options" later in this topic.

The recommended minimum size for the volume is 500 MB. It is recommended that you do not store user data on any volume in the quorum resource.

Before implementing your cluster, consider what type of quorum resource solution you plan to use. Take into consideration the following differences between single quorum device clusters and majority node set:

The failover behavior of the majority node set is significantly different from the behavior of the single quorum device model:

• Using the single quorum device model, you can maintain cluster availability with only a single operational node.
  
  
• If you use a majority node set, more than half, or (Number of nodes configured in the cluster/2) + 1 nodes must be operational to maintain cluster availability. The following table shows the number of node failures that a given majority node set cluster can tolerate yet continue to operate:
  
  

You would commonly use a single quorum resource model if all nodes in your cluster will be in the same geographical location. As part of this requirement, your nodes must be connected to the same physical storage device.

A majority node set on the other hand would typically be appropriate if you have geographically dispersed nodes. The cluster configuration data is stored locally on each node on a file share that is shared out to the other nodes on the network. However, those shares must always be accessible or nodes can fail.

There are other specific requirements for geographically dispersed clusters, including the requirement that round-trip latency of the network between cluster nodes be a maximum of 500 milliseconds. For information on cluster solutions that meet all requirements for a geographically dispersed cluster, refer to hardware compatibility information in the Windows Catalog at: http://go.microsoft.com/fwlink/?LinkId=37824

Microsoft supports only complete server cluster systems that are compatible with the Windows Server 2003 family of products. For both cluster models, confirm that your system or hardware components, including your cluster disks, are compatible with products in the Windows Server 2003 family by checking the hardware compatibility information in the Windows Catalog at: http://go.microsoft.com/fwlink/?LinkId=37824

This section tells how to obtain additional information about the majority node set model. For a diagram of a majority node set, see "Quorum Resource Options" earlier in this topic.

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If you are using a SCSI shared storage device, when you first attach your cluster hardware (the shared bus and cluster storage), be sure to work only from the firmware configuration screens on the cluster nodes (a node is a server in a cluster). On x86-based and x64-based computers, use the BIOS configuration screens. On Itanium-based computers, use the Extensible Firmware Interface (EFI) configuration screens. The instructions from your manufacturer will describe whether these configuration screens are displayed automatically or whether you must, after turning on the computer, press specific keys to access them. Follow the manufacturer’s instructions for completing the BIOS or EFI configuration process. Remain in the BIOS or EFI configuration screens, and do not allow the operating system to start, during this initial installation phase. Complete the following steps while the cluster nodes are still displaying BIOS or EFI configuration screens, before starting the operating system on the first cluster node.

• Make sure you understand and follow the manufacturer’s instructions for termination of the SCSI bus.
  
  
• Make sure that each device on the shared bus (both SCSI controllers and hard disks) has a unique SCSI ID. If the SCSI controllers all have the same default ID (often it is SCSI ID 7), change one controller to a different SCSI ID, such as SCSI ID 6. If there is more than one disk that will be on the shared SCSI bus, each disk must also have a unique SCSI ID. In addition, make sure that the bus is not configured to reset SCSI IDs automatically on startup (otherwise the IDs will change from the settings you specify).
  
  
• Ensure that you can scan the bus and see the drives from all cluster nodes (while remaining in the BIOS or EFI configuration screens).
  
  

• Turn on a single node. Leave all other nodes turned off.
  
  
• During this initial installation phase, remain in the BIOS or Extensible Firmware Interface (EFI) configuration process, and do not allow the operating system to start. While viewing the BIOS or EFI configuration screens, ensure that you can scan the bus and see the drives from the active cluster node. On x86-based and x64-based computers, use the BIOS configuration screens. On Itanium-based computers, use the EFI configuration screens. Consult the instructions from your manufacturer to determine whether these configuration screens are displayed automatically or whether you must, after turning on the computer, press specific keys to access them. Follow the manufacturer’s instructions for completing the BIOS or EFI configuration process.
  
  

If you have not already installed Windows Server 2003, Enterprise Edition, on the first cluster node, install it before proceeding. For information about decisions you must make, such as decisions about licensing and about the components to install, see "Getting Ready for a New Installation: Windows Server 2003, Enterprise Edition," on your Setup CD. For information about running Setup, see "Running Setup for a New Installation: Windows Server 2003, Enterprise Edition," on your Setup CD.

After you complete the BIOS or EFI configuration, start the operating system on one cluster node only, and complete the configuration of the Cluster service using Cluster Administrator.

With the Cluster Administrator New Server Cluster Wizard, you can choose between Typical (full) configuration and Advanced (minimum) configuration options. Typical configuration is appropriate for most installations and results in a completely configured cluster. Use the Advanced configuration option only for clusters that have complex storage configurations that the New Server Cluster Wizard cannot validate or for configurations in which you do not want the cluster to manage all of the storage. The following examples describe each situation:

• In some complex storage solutions, such as a fiber channel switched fabric that contains several switches, a particular storage unit might have a different identity on each computer in the cluster. Although this is a valid storage configuration, it violates the storage validation heuristics in the New Server Cluster Wizard. If you have this type of storage solution, you might receive an error when you are trying to create a cluster using the Typical configuration option. If your storage configuration is set up correctly, you can disable the storage validation heuristics and avoid this error by restarting the New Server Cluster Wizard, selecting the Advanced configuration option instead.
  
  
• On particular nodes in a cluster, you may want to have some disks that are to be clustered and some disks that are to be kept private. The Typical configuration option configures all disks as clustered disks and creates cluster resources for them all. However, with the Advanced configuration option, you can keep certain disks private because this configuration creates a cluster in which only the quorum disk is managed by the cluster (if you chose to use a physical disk as the quorum resource). After the cluster is created, you must then use Cluster Administrator to add any other disks that you want the cluster to manage.
  
  

If you are using a shared storage device: Before creating a cluster, when you turn the computer on and start the operating system, it is very important that only one node has access to the cluster disk. Otherwise, the cluster disks can become corrupted. To prevent the corruption of the cluster disks, shut down all but one cluster node, or use other techniques (for example, LUN masking, selective presentation, or zoning) to protect the cluster disks before creating the cluster. Also, before starting the installation of the second and subsequent nodes, ensure that all disks that are to be managed by the cluster have disk resources associated with them. If these disks do not have disk resources associated with them at this time, the disk data will be corrupted because the disks will not be protected and multiple nodes will attempt to connect to them at the same time.

To create and configure a cluster after unattended Setup, run a script to invoke the cluster /create: command and supply all the necessary configuration information on the command line. For more information on creating a cluster using unattended installation, after you install Windows Server 2003, Enterprise Edition, see "To create a cluster" in Help and Support Center. To open Help and Support Center, after completing Setup, click Start, and then click Help and Support. Also, see the Windows Server 2003 Deployment Kit, especially the "Designing Unattended Installations" topic in Automating and Customizing Installations.

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