We have a 64bit virtual machine (CentOS) that we'd like to run on 64bit host-machine (may be running under any OS), but that host-machine doesn't support hardware virtualization, which, you know, should be for running 64bit virtual machines in it.

I tried VirtualBox and VMware Player, but they both have this issue with non-hardware-virtualization processor. I thought maybe another virtualization system may help, like OpenVZ or XEN or KVM? What do you think?

At Stackoverflow I was advised to use Qemu. Won't OpenVZ or XEN or KVM work? We just wanted to try one of these software, if one of them can solve this problem.


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    qemu completely virtualises everything, so it can even run utterly incompatible and different architectures. The tradeoff here is performance. I do seem to recall you should be able to run 64 bit VMs on 64bit systems with no issues, but i may be wrong – Journeyman Geek May 29 '12 at 14:22
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    It may be easiest to replace the offending processor. – Michael Hampton Aug 11 '12 at 18:14

Probably not, or at least, no easy, well-supported way.

See http://en.wikipedia.org/wiki/X86_virtualization#Software-based_virtualization which says

The initial version of x86-64 (AMD64) did not allow for a software-only full virtualization due to the lack of segmentation support in long mode, which made the protection of the hypervisor's memory impossible, in particular, the protection of the trap handler that runs in the guest kernel address space.[12][13]:11 and 20 Revision D and later 64-bit AMD processors (as a rule of thumb, those manufactured in 90 nm or less) added basic support for segmentation in long mode, making it possible to run 64-bit guests in 64-bit hosts via binary translation. Intel did not add segmentation support to its x86-64 implementation (Intel 64), making 64-bit software-only virtualization impossible on Intel CPUs,


If you can sacrifice performance, you can try with full CPU emulators like QEMU or Bochs. With QEMU, you can use almost any kind of CPU as guest or host. With Bochs the guest can be x86 or x86-64, and the host can be any kind of CPU.


Take a look at LXC or OpenVZ.

It offers container based virtualization with no need of a processor with VT instructions. This virtualization causes almost no overhead.

LXC is very similar to OpenVZ, with VM being compatible with the 2 technologies. LXC is a more recent project.



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