hardMultiple ChoiceObjective-mapped

AZ-400 Practice Question: Refer to the exhibit

Exhibit

Resource Group: rg-devops
Location: eastus

Properties:
  provisioningState: Succeeded
  platformFaultDomainCount: 2
  platformUpdateDomainCount: 5
  virtualMachines:
    - id: /subscriptions/.../vm1
    - id: /subscriptions/.../vm2
  statuses:
    - code: AvailabilityState
      level: Warning
      displayStatus: Degraded
      message: 'VM vm1 is not running on the fault tolerant infrastructure due to an ongoing platform event.'

Refer to the exhibit. You have an availability set with two VMs. One VM shows a degraded availability state. What is the most likely impact on application availability?

⚠ Common exam trap

Watch out — candidates often assume a single degraded VM has no impact because the other VM is healthy, but they overlook that the degraded VM is at risk of failure, which can reduce application resilience or capacity.

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

✓

The application will be vulnerable to unplanned hardware failures that affect the degraded VM's host.

In an availability set, VMs are placed on different fault domains (separate racks with independent power, cooling, and network) to protect against unplanned hardware failures. If one VM shows a degraded availability state, it indicates that its underlying host or hardware is experiencing issues, making that VM vulnerable to failure. The other VM remains healthy, but the application is not fully resilient because the degraded VM could fail, reducing the application's capacity or causing partial downtime if the application requires both VMs to handle load.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

✗
The application will be fully resilient to both planned and unplanned maintenance events.
Why it's wrong here
Incorrect. An availability set with two VMs provides protection only when both VMs are healthy and placed in separate fault domains. The degraded VM is not on fault-tolerant infrastructure, meaning an unplanned hardware failure on its host can take it down. Therefore, the application is not fully resilient to unplanned maintenance events, even though planned maintenance is handled by update domains.
✓
The application will be vulnerable to unplanned hardware failures that affect the degraded VM's host.
Why this is correct
Correct. Because the degraded VM is not on fault-tolerant infrastructure, its host is not guaranteed to be isolated from hardware failures. If that host experiences an unplanned failure, the VM will shut down unexpectedly. Since the other VM cannot necessarily absorb the full workload, the application is vulnerable to downtime or degraded performance during such an event.
✗
The application will experience downtime during planned maintenance events.
Why it's wrong here
Incorrect. Planned maintenance in Azure is handled via update domains, and an availability set typically has five update domains. With two VMs distributed across different update domains, Microsoft reboots each update domain sequentially, ensuring at least one VM stays online. Thus, planned maintenance should not cause downtime for the application.
✗
The application will continue to run without any impact because the other VM is healthy.
Why it's wrong here
Incorrect. Although the healthy VM remains online, the degraded VM is at risk of failure due to its host's lack of fault tolerance. If the degraded VM fails, the application loses that instance and may become unavailable or experience severe performance issues if the healthy VM cannot handle the entire workload alone. The application is therefore impacted by the potential failure of the degraded VM.

Go deeper

AZ-400 Practice Question: Refer to the exhibit

Exhibit

Why each option matters

Option-by-option breakdown

Related to this question