<ul><li>High-availability clusters (also known as HA Clusters or Failover Clusters) are computer clusters that are implemented primarily for the purpose of providing high availability of services which the cluster provides.
They operate by having redundant computers or nodes which are then used to provide service when system components fail.</li></ul>INTRODUCTION<br />
Working of HA Cluster<br /><ul><li> Redundancy for fault tolerance
Failover - if 1 node </li></ul> shuts down or fails, another node takes over application load<br /><ul><li>Facilitates planned maintenance </li></li></ul><li>CLUSTOR NETWORK<br />
<ul><li>Users & businesses have high expectations</li></ul>Reliability - high degree of protection for corporate data. Information is a crucial business asset.<br />Availability - near continuous data access<br />Serviceability - procedures to correct problems with minimal business impact<br />Reliability, Availability, Serviceability (RAS)<br />
FAIL_FAST: The try fails, if the first node cannot be reached.<br />ON_FAIL_TRY_ONE_NEXT_AVAILABLE: Tries one more host before giving up<br />ON_FAIL_TRY_ALL_AVAILABLE: Tries all existing nodes before giving up<br />Fail Over Strategies<br />
Applications of HA Cluster<br />Used for critical databases, file sharing, e-commerce websites.<br /> heartbeat private network connection which is used to monitor the health and status of each node<br /> Split brain condition must be solved<br /> Various Node configurations<br />