IBM Reliable Scalable Cluster Technology (RSCT) is a set of software components that together provide a comprehensive clustering environment for AIX, Linux, Solaris, and Windows operating systems. RSCT is the infrastructure used by a variety of IBM products to provide clusters with improved system availability, scalability, and ease of use. It follows a list of main RSCT components:

• the Resource Monitoring and Control (RMC) subsystem. This is the scalable, reliable backbone of RSCT. It runs on a single machine or on each node (operating system image) of a cluster and provides a common abstraction for the resources of the individual system or the cluster of nodes. You can use RMC for single system monitoring, or for monitoring nodes in a cluster. In a cluster, however, RMC provides global access to subsystems and resources throughout the cluster, thus providing a single monitoring/management infrastructure for clusters. It is used for HMC DLPAR, sfp, invscout ...
• the RSCT core resource managers. A resource manager is a software layer between a resource (a hardware or software entity that provides services to some other component) and RMC. A resource manager maps programmatic abstractions in RMC into the actual calls and commands of a resource.
• the RSCT cluster security services, which provide the security infrastructure that enables RSCT components to authenticate the identity of other parties.
• the Topology Services subsystem, which, on some cluster configurations, provides node/network failure detection.
• the Group Services subsystem, which, on some cluster configurations, provides cross node/process coordination.