Microsoft Cluster Server

Microsoft Cluster Server (MSCS) is a computer program that allows <a href="/facts/Server_(computing)/dEaYFD7r">server computers</a> to work together as a <a href="/facts/Computer_cluster/mT7S1BcX">computer cluster</a>, to provide <a href="/facts/Failover/Lw0rXfv9">failover</a> and increased availability of applications, or <a href="/facts/Parallel_computer/nQzcpzQt">parallel calculating power</a> in case of <a href="/facts/High-performance_computing/HT9NwGAN">high-performance computing (HPC)</a> clusters (as in <a href="/facts/Supercomputing/HT9NwGAN">supercomputing</a>).
Microsoft has three technologies for clustering: Microsoft Cluster Service (MSCS, a <a href="/facts/High-availability_cluster/MNWwE5RX">HA clustering</a> service), <a href="/facts/Component_Object_Model/2DtIAufW">Component</a> Load Balancing (CLB) (part of Application Center 2000), and <a href="/facts/Network_Load_Balancing_Services/cVJ1dsf9">Network Load Balancing Services</a> (NLB). With the release of <a href="/facts/Windows_Server_2008/hrcPjTCH">Windows Server 2008</a> the MSCS service was renamed to Windows Server Failover Clustering (WSFC), and the <a href="/facts/Load_balancing_(computing)/jddk6ang">Component Load Balancing</a> (CLB) feature became deprecated.
Prior to Windows Server 2008, clustering required (per Microsoft KBs) that all nodes in the clusters to be as identical as possible from hardware, drivers, firmware, all the way to software. After Windows Server 2008 however, Microsoft modified the requirements to state that only the operating system needs to be of the same level (such as patch level).

Microsoft Cluster Server open-in-new

Microsoft Cluster Server