What happens in the event of a primary host failure when using vSphere Fault Tolerance?

In a vSphere Fault Tolerance configuration, the system is designed to provide continuous availability for virtual machines. When a primary host fails, the secondary virtual machine is already running in lockstep with the primary instance, allowing it to seamlessly take over operations without any interruption. This means that the failover happens automatically and instantly, ensuring that end users experience no downtime and that business operations continue as intended.

Fault Tolerance works by creating a secondary instance of a VM that is continuously updated with the same state as the primary VM. As soon as a failure is detected in the primary host, the secondary VM automatically becomes the new primary VM, thus maintaining operations without requiring any manual intervention or significant delay.

Understanding this functionality is key for those managing critical workloads in a virtualized environment. It ensures high availability and protects against data loss without the need for additional administrative effort during a failure scenario.