Microsoft is developing cluster application programming interfaces (APIs) that allow applications to take advantage of Windows NT Server in a clustered environment. The company will deliver clustering products in two phases:
A fail-over solution improves data availability by allowing two servers to share the same hard disks within a cluster. When a system in the cluster fails, the cluster software will recover and disperse the work from the failed system to another server within the cluster. As a result, the failure of a system in the cluster will not affect the other systems, and in most cases, the client applications will be completely unaware of the failure. This means high server availability for the users. Phase 1 clusters will become available in the first half of 1997.
Phase 2 will enable more than two servers to be connected together for higher performance and reliability. As a result, when the overall load exceeds the capabilities of the systems in the cluster, additional systems may be added to the cluster. This incremental growth enables customers to easily add processing power as needed.
Cluster features will be integrated into existing Windows NT Server system management tools to enable system administrators who are already familiar with Windows NT Server systems to easily setup and configure their clusters. The initial product will include base operating system support for clusters, including components to configure, maintain, and monitor membership in the cluster, support for a cluster-wide name-space, communication, and fail-over support. Additional services will support the two primary cluster software models. As with all of the distributed services provided by Windows NT Server, ease of setup and cluster management tools will be a very high priority.