VMWare ESX – Hot add RAM does not showing the new value inside Windows Server 2016

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A server stack is the collection of software that forms the operational infrastructure on a given machine. In a computing context, a stack is an ordered pile. A server stack is one type of solution stack — an ordered selection of software that makes it possible to complete a particular task. Like in this post about VMWare ESX – Hot add RAM does not showing the new value inside Windows Server 2016 was one problem in server stack that need for a solution. Below are some tips in manage your windows server when you find problem about windows, vmware-esxi, vmware-vsphere, hotswap, .

I have VMware ESXi, 6.7.0, 17098360 server in my environment. Recently I tried Hot Add RAM with one of my Microsoft Windows Server 2016 VMs.

I successfully increased from 16 GB to 24 GB but inside the guest OS console it’s not showing as 24 GB still the old value 16 GB.

Why is this issue occurring?

  • No any RAM limit inside VMWare

  • Installed latest VMWare Tools

  • No any vNUMA issue

Background from my Knowledge

Hot-Adding Memory or CPU never worked for me on any Windows VM’s due to the past Years.
A Scheduled Downtime for an Off/On was always Required

Reference: VMware KB52584

Original Statement:

Virtualization Based Security (VBS) is a new feature introduced in
Windows 10 and Windows Server 2016. vSphere supports running Windows
with VBS enabled starting in the vSphere 6.7 release. However, hot-add
memory and CPU will not operate for Windows virtual machines when
Virtualization Based Security (VBS) is enabled in the OS.


To resolve this issue, power off the virtual machine to make Memory and CPU changes.


This affect mostly also the Hot-Add of CPU’s imho.

Reference for Other Links

Microsoft page: Virtualization Based Security (VBS) in Gerneral

This Answer should be more Generic, but its also Specific to your Question also 😉

I hope i could help you with your Question and would be glad if you accept and upvote it 🙂

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