Memory reservation warning when editing settings of some virtual machines using the vSphere Client in vCenter 7 Update 2 or later

Products

• VMware vCenter Server

Issue/Introduction

Symptoms:

When navigating to the Edit Settings form of a VM that has "Reserve all guest memory (All locked)" checked, you might see a red exclamation mark next to the reservation value. On mouse-over, the description states: 

"Reservation must be between 0 MB and X MB."

Where X is the correct displayed reservation and assigned memory in MB. This warning was not visible on vSphere Client releases before vCenter 7.0.2.

Environment

VMware vCenter Server 7.0.3
VMware vCenter Server 7.0.2

Cause

This false positive is caused by an issue in the memory reservation validation logic.

Resolution

This is currently being investigated, to be informed about updates to this KB, please subscribe to it.

Workaround:
If you need to reduce the reservation of the virtual machine, toggle the reservation unit to GB and back to MB to reset the validation logic.

Additional Information

Impact/Risks:
This is an UI issue only and does not impact the actual reservation, it is still locked to the virtual machines assigned memory. When unchecking "Reserve all guest memory (All locked)" and trying to change the reservation, the "OK" button might remain greyed out.