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Nest virtualization failed with VT-x is not available error

VMware ESXi (vSphere) is not officially supported, but you can use nested virtualization for verification. Using this, I thought of installing Ubuntu (Linux) as a guest OS of ESXi, and using VirtualBox within it.

Eventually I wanted to use PCF Dev (Pivotal Cloud Foundry Develop), but failed nested virtualization failed and failed ...

PCF Dev(Cloud Foundry) install to Home LinuxVM - designetwork(EN)

Server Spec

The tested environment is as follows. The guest OS uses Ubuntu, but it failed in error regardless of Windows or Linux.

  • Physical server

  • Virtual server Ubuntu 16.04.1 (Linux)

    • CPU: 1 CPU 2 core
    • Memory: 3 GB
    • DISK: 64 GB
    • Virtual Box 5.1

Setting for nesting ESXi

In order to have a nested configuration, additional configuration is required. Activate VT-x of the guest OS as follows and restart the service.

# vi /etc/vmware/config

libdir = "/usr/lib/vmware"
authd.proxy.nfc = "vmware-hostd:ha-nfc"
authd.proxy.nfcssl = "vmware-hostd:ha-nfcssl"
authd.proxy.vpxa-nfcssl = "vmware-vpxa:vpxa-nfcssl"
authd.proxy.vpxa-nfc = "vmware-vpxa:vpxa-nfc"
authd.fullpath = "/sbin/authd"
vhv.enable = TRUE    // add

# /etc/init.d/hostd restart
watchdog-hostd: Terminating watchdog process with PID 98940
hostd stopped.
Ramdisk 'hostd' with estimated size of 127MB already exists
hostd started.
~ #

By default, vSphere's guest OS does not have VT-x enabled. Poweroff the virtual machine and change the setting. "CPU / MMU virtualization" in the "Options" tab defaults to "Automatic" "Intel VT-x / AMD-v used for instruction set virtualization and software to MMU virtualization Use"is selected. Work in the order of virtual machine poweroff> change setting> virtual machine power on.

VT-x is not available

I encountered an error in the above PCF Dev installation.


Error: failed to start VM: failed to execute 'VBoxManage startvm pcfdev-v0.389.0 --type headless': exit status 1: VBoxManage: error: VT-x is not available (VERR_VMX_NO_VMX)
VBoxManage: error: Details: code NS_ERROR_FAILURE (0x80004005), component ConsoleWrap, interface IConsole
Waiting for VM "pcfdev-v0.389.0" to power on...

VBoxManage: error: VT-x is not available (VERR_VMX_NO_VMX)

It seems that VT-x (CPU virtualization mechanism) is not working.

vSphere Client Error

The guest OS is powered off and looking at the summary screen, it is in the following state. I can not start the virtual machine. Such errors are displayed on the summary screen.

Virtualized Intel VT-x / EPT is not supported on this platform. Continue without using virtual

However, an error occurred when trying to power on. Failure ...

Virtual requires the priority mode of It is returning to automatic.

CPU (Core 2 Quad) does not support guest virtualization

I found the following discussion when I was investigating without knowing the cause.

According to here, Core 2 Quad does not support Nested VM ...

Core 2 systems do not support EPT, so you will not be able to run nested 64-bit VMs.


Core 2 Quad (Duo) can not use nested virtualization. I need to change to CPU of Core i series or higher.

This Blog is English Version of my JP's.

Sorry if my English sentences are incorrect.