Introduction

Downtime always brings significant costs to any environment. Thus, implementing a high availability solution is always necessary. However, traditionally it brings complexity, in terms of manageability and cost.

VMware vSphere High Availability (vSphere HA) makes it simpler, easier, and cheaper to provide high availability for your important applications. You can configure it with a couple of simple steps through VMware vCenter Server. You can create a vSphere HA Cluster with multiple ESXi Servers, which will enable you to protect virtual machines and the services running inside them. In the event of a failure of one of the hosts in the cluster, impacted virtual machines are automatically restarted on other ESXi hosts within that same VMware vSphere Cluster.

However, it is not that easy to determine size of a vSphere HA Cluster, keeping an amount of resource in a safe vault, and considering some other features such as vSphere Fault Tolerance (also known as FT) and Distributed Power...