What Does High Availability Cluster (HA Cluster) Mean?
A high availability cluster (HA cluster) is a set of computer hardware pieces that provide solutions for redundant operations, in the event of network component failure. Many HA cluster systems are designed to support enterprises that cannot afford to have critical interruptions to business processes if a single computer or server goes down, or if a single office is compromised in an emergency situation.
Techopedia Explains High Availability Cluster (HA Cluster)
HA clustering is part of a clustering strategy for redundant operations. IT professionals tie various pieces of hardware together in a redundant system so that hardware pieces can perform failover duties if other pieces fail. These types of setups support the idea of fault tolerant systems that allow businesses to continue regular operations - even during emergencies or crises that take out some of their operating hardware.
IT professionals often talk about clustering in terms of server functionality. HA cluster systems must be calibrated and installed in specific ways. In many cases, it is recommended that all of the machines share the same network virtualization system. Commonly, hardware pieces in the cluster have access to shared storage locations using data transmission systems, like fiber channel or small computer system interface (SCSI).