“High Availability” is the term coined with uptime. This is a method designed to increase the availability of services to the client, and thus provides more reliable servers/services for critical applications.

There are many enterprise grade open-source free applications available for implementing the high availability concept. The cluster suite provided with RHEL, CentOS is packed with bunch of kernel level and user level tools to implement high availability, also there are many other popular tools like heartbeat, pacemaker, drbd etc which helps to get reliable nodes and services.

The complexity of high availability tools makes it slightly difficult to understand and implement the technology. The aim of this article is to provide an overview of cluster/high availability applications. This will help you figure out the challenging task of how to best manage and provide high availability! Continue reading →