VERR_VMX_MSR_VMXON_DISABLED when starting an image from Oracle virtual box

Question

I'm getting this error while loading a Puppet image from a Oracle virtual box. How can I fix it?

Failed to open a session for the virtual machine learn-puppet-centos-6.4-pe-3.1.0.  VT-x is disabled in the BIOS. (VERR_VMX_MSR_VMXON_DISABLED).  Result Code: E_FAIL (0x80004005) Component: Console Interface: IConsole {8ab7c520-2442-4b66-8d74-4ff1e195d2b6} 

In addition, I see that the acellerate-tab in Virtual Box is disabled.

Answer 1

I believe VirtualBox is throwing this error for a number of reasons. Very annoying that it's one error for so many things but, I guess it's the same requirement it's just that the root cause is different.

Potential gotchas:

1. You haven't enabled VT-x in VirtualBox and it's required for the VM.
   • To enable: open vbox, click the VM, click Settings..., System->Acceleration->VT-x check box.
2. You haven't enabled VT-x in BIOS and it's required.
   • Check your motherboard manual but you basically want to enter your BIOS just after the machine turns on (usually DEL key, F2, F12 etc) and find "Advanced" tag, enter "CPU configuration", then enable "Intel Virtualization Technology".
3. Your processor doesn't support VT-x (eg a Core i3).
   • In this case your BIOS and VirtualBox shouldn't allow you to try and enable VT-x (but if they do, you'll likely get a crash in the VM).
4. Your trying to install or boot a 64 bit guest OS.
   • I think 64 bit OS requires true CPU pass-through which requires VT-x. (A VM expert can comment on this point).
5. You are trying to allocate >3GB of RAM to the VM.
   • Similar to the previous point, this requires: (a) a 64 bit host system; and (b) true hardware pass-through ie VT-x.

So for my little mess around machine that I'm resurrecting that has 8GB RAM but only a ye-olde Core i3, I'm having success if I install: 32 bit version of linux, allocating 2.5GB RAM.

Oh, and wherever I say "VT-x" above, that obviously applies equally to AMD's "AMD-V" virtualization tech.

I hope that helps.