How to Configure Two-Node High Availability Cluster On RHEL/CentOS 7.6

This article will help you learn how to setup and configure a High-Availability (HA) cluster on Linux/Unix-based systems.

Cluster is nothing but a group of computers (called nodes/members) to work together to execute a task. Basically there are four types of clusters available, which are Storage Cluster, High-availability Cluster, Load-balancing Cluster, and HIGH-Performance Computing Cluster. In production, HA (High-Availability) and LB (Load Balancing) Clusters are the most deployed cluster types in the clustered environment. They offer, uninterrupted availability of services/data as they can be (for eg: web services) to the end-user community. HA Cluster configurations are sometimes grouped into two subsets: (Active-active and Active-passive).

Active-active: Typically you need a minimum of two nodes, both nodes should be running the same service/application actively. This is mainly used to achieve Load Balancing (LB) Cluster to distribute the workloads across the nodes.