VMware Fault Tolerance provides continuous availability for virtual machines by creating and maintaining a secondary VM that is identical to, and continuously available to replace, the primary VM in the event of a hardware outage.
The Primary and Secondary VMs continuously exchange heartbeats. This exchange allows the virtual machine pair to monitor the status of one another to ensure that fault tolerance is continually maintained. A transparent failover occurs if the host running the Primary VM fails, in which case the Secondary VM is immediately activated to replace the Primary VM.
A new Secondary VM is then started and Fault Tolerance redundancy is re-established within a few seconds. If the host running the Secondary VM fails, it is also immediately replaced. In either case, users experience no interruption in service and no loss of data.
VMware Fault Tolerance is used by companies to prevent application disruption due to hardware failures. Downtime associated with mission-critical enterprise applications can be very expensive and disruptive to businesses. Traditional solutions that address this problem through hardware redundancy or clustering are complex and expensive. VMware HA addresses server failures by automatically restarting virtual machines on alternate servers. VMware Fault Tolerance takes high availability to the next level, completely eliminating downtime due to hardware failures with simplicity, at a low cost and across all applications, regardless of operating system.
Advantages of VMware Fault Tolerance
- Eliminate even the smallest of disruptions due to server hardware failures.
- Provide continuous availability to any critical application
- Deliver uninterrupted service with simplicity and low cost
- Transparent failover with no data or state loss in the virtual machine