Windows 2008 Failover Cluster Preparation article

A failover cluster must meet certain requirements of the hardware, software, and network infrastructure, and it requires an administrative account with the appropriate domain permissions. Specifically as follows:

(i) Hardware requirements for failover clusters

In a failover cluster, the following hardware is required:

(1) Server: It is recommended that you use a set of matching computers that contain the same or similar components.

Note that Microsoft supports failover clustering solutions only if all hardware components are marked "Certified for Windows Server 2008". In addition, the full configuration (server, network, and storage) must pass all the tests in the Validate Configuration Wizard, which is included in the failover cluster snap-in.

(2) network adapters and cables (for network traffic): As with other components in a failover clustering solution, network hardware must be marked "Certified for Windows Server 2008". If you use iSCSI, you must have a network adapter dedicated to network traffic or iSCSI, not both.

In the network infrastructure that connects the cluster nodes, avoid having a single point of failure. There are several ways to achieve this. You can connect to cluster nodes through multiple different networks. Alternatively, you can connect to a cluster node over a network consisting of a group of network adapters, redundant switches, redundant routers, or similar hardware that eliminates single points of failure.

Note: If you are connecting to a cluster node through a network, the network needs to meet the redundancy requirements in the Authentication Configuration Wizard. However, the report in the wizard will contain a warning indicating that the network should not have a single point of failure.

(3) Device controller or appropriate adapter for storage:

-for serial attached SCSI or Fibre Channel: If you are using serial attached SCSI or Fibre Channel on all clustered servers, the mass storage device controller that is dedicated to the cluster storage device should be the same. They should also use the same firmware version.

Note: Through Windows Server 2008, you cannot use parallel SCSI to connect storage to a clustered server.

-For iSCSI: If you are using iSCSI, each cluster server must have one or more network adapters or host bus adapters dedicated to the cluster storage device. The network used for ISCSI cannot be used for network traffic. In all clustered servers, the network adapters used to connect to the ISCSI storage targets should be the same, and Gigabit Ethernet or higher-speed Ethernet is recommended.

For iSCSI, you cannot use a group of network adapters because they are not supported by iSCSI.

-Storage: You must use shared storage that is compatible with Windows Server 2008.

In most cases, the store should contain multiple stand-alone disks (LUNs) configured at the hardware level. For some clusters, use a disk as the witness disk. Other disks contain the files required by the Cluster service or application. Storage requirements include the following:

-To use the native disk support that is included in a failover cluster, use a basic disk instead of a dynamic disk.

-It is recommended that you format the partition in NTFS format (the partition must be in NTFS format for the witness disk).

-For the partition form of the disk, you can choose to use the Master boot record (MBR) or use the GUID partition table (GPT).

The witness disk is a disk in the cluster storage that is specified to hold a copy of the cluster configuration database. A failover cluster will have a witness disk only if the witness disk is specified as part of the quorum configuration.