Oracle Solaris Cluster is a high-availability cluster software product for Solaris, originally created by Sun Microsystems, which was acquired by Oracle Corporation in 2010. It is used to improve the availability of software services such as databases, file sharing on a network, electronic commerce websites, or other applications. Sun Cluster operates by having redundant computers or nodes where one or more computers continue to provide service if another fails. Nodes may be located in the same data center or on different continents.

Sun Microsystems, Inc. was an American technology company that sold computers, computer components, software, and information technology services and created the Java programming language, the Solaris operating system, ZFS, the Network File System (NFS), and SPARC microprocessors. Sun contributed significantly to the evolution of several key computing technologies, among them Unix, RISC processors, thin client computing, and virtualized computing. Notable Sun acquisitions include Cray Business Systems Division, Storagetek, and Innotek GmbH, creators of VirtualBox. Sun was founded on February 24, 1982. At its height, the Sun headquarters were in Santa Clara, California, on the former west campus of the Agnews Developmental Center.