Microsoft Azure Administrator Associate AZ-104 Practice Question

The load balancer's health probe needs to reach the backend virtual machines on a specific port to determine their health. If the Network Security Group (NSG) associated with the VMs does not allow inbound traffic on the probe port, the health probes will fail, marking the VMs as unhealthy. By configuring the NSG to permit inbound traffic on the probe port, the health probes can succeed, and the load balancer can properly distribute traffic to the healthy backend instances.

Changing the probe type from TCP to HTTP may not resolve the issue if the NSG is still blocking the port. Adding the virtual machines to an availability set is related to high availability but does not affect the health probe status. Enabling session persistence affects how traffic is distributed but does not influence health probe connectivity.