Citrix Power Actions failing on Nutanix due to Guest Agent Impact with the Operating System Power Settings

book

Article ID: CTX696877

calendar_today

Updated On:

Description

When Citrix Studio or Autoscale issues a power action (Restart, Shut Down, Force Restart), the Delivery Controller sends the request to the hypervisor via the hosting connection. The hypervisor translates this into an ACPI power-button event delivered to the Windows guest OS. The hypervisor accepts the request before the guest OS processes it, so the Delivery Controller receives a successful acknowledgment. The broker then waits for the VDA to reflect the expected power state. When the guest OS discards the ACPI signal, the VDA remains powered on and registered, creating a mismatch between the expected and actual power state visible in Studio and Director. No error is returned at any layer, making the failure silent from the administrator's perspective.

In pooled VDI environments, the probability of encountering this condition across a large fleet is significantly higher than in persistent or server-based workloads, particularly when gold images ship with default Windows power settings or screensaver policies.

Cause

 
The Windows guest OS silently discarded the ACPI shutdown signal. Windows can ignore ACPI power-button events under several conditions:

    1. Active screensaver - Windows treats the incoming ACPI event as user input, dismissing the screensaver instead of initiating a shutdown or reboot. A subsequent power action will succeed only if it is received before the screensaver reactivates.
    2. Power button action not set to Shut Down - If the Windows power button behavior is configured to Sleep, Do Nothing, or any option other than Shut Down, the OS may ignore the ACPI shutdown signal entirely.
    3. Power service disabled or stopped - If the Windows Power service is not running, the OS cannot process power plan policies or respond to ACPI power-button events, causing the action to be silently dropped.

Resolution

Apply the following configuration changes to the gold/master image used by the affected Machine Catalog, then update the catalog to push the new image to pooled VDAs:

  1. Disable the screensaver - Navigate to Settings > Personalization > Lock screen > Screen saver settings. Set Screen saver to (None). Additionally, under Power Options > Change plan settings, set "Turn off the display" to Never.
    • image.png
  2. Set power button action to Shut Down - Navigate to Control Panel > Power Options > Choose what the power button does. Set "When I press the power button" to Shut Down.
    • image.png
  3. Ensure the Power service is running - Open Services (services.msc), locate the Power service, set Startup type to Automatic, and start the service if it is stopped.
  4. Optional: Enable forced shutdown via power button - If the above settings do not resolve the issue, a forced shutdown on ACPI power-button press can be enabled by running the following from an elevated command prompt:
    • powercfg -attributes SUB_BUTTONS 833a6b62-dfa4-46d1-82f8-e09e34d029d6 -ATTRIB_HIDE
    • Then navigate to Power Options > Change plan settings > Change advanced power settings > Power buttons and lid, and set all options to On.
      • Note: This will shut down the VM without giving users the opportunity to save unsaved work.


Issue/Introduction

Power management actions initiated through Citrix Studio (e.g., Restart, Shut Down) may silently fail to complete on target VDAs. The hypervisor acknowledges the request, and no errors are surfaced in Studio or Director. Affected machines may show a stale power state or remain stuck in a "Turning Off" or "Turning On" transitional state in Studio indefinitely. Subsequent attempts to perform the same action on the same machine may succeed. This behavior is observed more frequently in pooled VDI environments with large machine counts.

Additional Information

https://portal.nutanix.com/page/documents/kbs/details?targetId=kA00e000000LJZSCA4

Powered by Wolken Software