A vSphere cluster hosts a three-tier application. The cluster has 50% resources available. If a host in the cluster fails, the database server must be online before the application server, and the…

Predictive DRS proactively balances workloads based on anticipated resource needs to prevent future resource contention, not to manage VM restart order after a host failure.

vSphere HA Orchestrated Restart allows administrators to define dependencies between virtual machines, ensuring that they restart in a specific order. This feature is crucial for multi-tier applications where one tier, like a database server, must be available before dependent tiers, such as application servers, can start successfully.

vSphere HA Restart Priority assigns a relative priority (e.g., high, medium, low) to VMs for restarting after a host failure, but it does not allow for defining specific start-up dependencies between them.

Proactive HA works by identifying and evacuating VMs from hosts experiencing hardware issues-before-a complete failure occurs, aiming to prevent downtime rather than orchestrating restarts after a failure.