To ensure high availability for distributed applications such as load-balanced web servers, Nutanix AHV allows administrators to configure Anti-Affinity rules.

An Anti-Affinity rule specifies that a group of virtual machines should never run on the same AHV host simultaneously. By applying an Anti-Affinity rule to the three web server VMs, the Acropolis Scheduler ensures they are distributed across different physical nodes in the cluster.

In the scenario described, the web servers likely resided on the same host (or the failing host held the only active instance). If Anti-Affinity rules had been configured, the other web server VMs would have been running on healthy hosts, ensuring continued user access to the VDI environment despite the single node failure.