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Can we install a KVM machine on a virtualbox machine??? Virtual Machine on a Virtual Machine

I get the following error when I issue: $ virt-install –-name kvm_client1 –-ram 256 –-disk path=/var/lib/libvirt/images/kvm_client1.img,size=5 –-network network=default –- cdrom /dev/cdrom

ERROR No 'Guest' class for virtualization type 'lxc'

I'm using a RHEL 6.0 on a Virtual Box virtual machine

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up vote 8 down vote accepted

KVM needs VT, because you are in a virtual machine this is not possible to get to. Hence it is not possible to run KVM in virtualbox.

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Thans @Lucas. I am new to Linux and as such was not sure. You helped me clear the clogs up there ;-) Cheers!!! – Anshuman Mar 21 '12 at 15:19
This is actually due to VT not being automatically inherited by the guest - it is technically possible, currently is not implemented in VirtualBox, but it is in other virtualization software. The related bug ticket is #4032. – ignis Jan 25 '13 at 22:28

KVM supports several types of virtualization libraries. Depending on your host machine, these libraries use by default a virtualization CPU capability that is possibly not available inside your virtualbox Host.

  • If you have an AMD CPU with SVM (Secure Virtual Machine) you can use a nested kvm.
  • If you have an Intel CPU with VT-x (Virtualization Technology), it depends on the system you have. The required drivers was released recently and possible you must upgrade the system (or may be install other OS, such as CentOS, instead RHEL)

To enable nested vm on Intel CPUs you can check

NOTE: As I know, Red Hat doesn't support these new KVM kernels.

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It is possible, New feature called nested kvm is availble for a amd processor. you can learn more here

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The question was specifically regarding KVM on top of vbox. Nested KVM adds "VT" instructions to KVM so that it can support nested hypevisors, that doesn't help support anything nested under vbox. – Joshua Hoblitt May 6 '12 at 21:24
I tried before I know the theory, it's impossible. – warl0ck Sep 6 '12 at 8:46

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