I have a guest VM that I've created in the vSphere Client (5.5), which has Ubuntu Linux 14.4 64-bit installed as the operating system.
I'm wondering if it is possible for that VM to host a hypervisor such as VirtualBox, which would then be capable of creating 64-bit VMs. (A 64-bit VM inside a 64-bit VM, basically.)
On the Ubuntu Linux VM, I have installed the latest version of VirtualBox (5.0.16 r105871), but when I attempt to create a new guest within VirtualBox, only 32-bit operating systems are listed in the available options.
I have seen some documentation suggesting that 64-bit guest VMs can only be created if there is hardware support for virtualization enabled (see "Known Issues" on this page: VirtualBox/Installation - Community Help Wiki) -- how can I enable this in the VM that was created in the vSphere Client?
I have tried messing with the VM settings (right click on VM in vSphere, go to 'Edit Settings', select 'Options' tab, then change the settings for 'CPU/MMU virtualization') but this doesn't have any impact (I'm guessing that this refers to the relationship between ESX and the VM, not the VM itself).
I've tried booting the VM into BIOS, but there are no settings in the BIOS related to virtualization.
Any advice would be appreciated.