virtualbox and bhyve questions

Peter Grehan grehan at
Wed Apr 2 18:33:41 UTC 2014

Hi John,

> 1. I've read that virtualbox and bhyve cannot run at the same time. Is
> this still the case? (because I've managed to start a bhyve instance
> with virtualbox still running - is this a fluke?)

  If you use VirtualBox with VT-x disabled, i.e. binary translation 
mode, it will work.

  Otherwise, all bets are off. There is no way to share VT-x resources 
(vCPU TLB tags, CPU VMCS state etc) so eventually the hypervisors will 

> 2. Can I take a system made in virtualbox and boot with it using bhyve?
> The system 'hard drives' are all VDI (the default in virtualbox)

  You would have to convert the VDI file to a flat file with a tool like 
qemu-img. Depending on the o/s, the disk and network adapter type may 
have to be the same in vbox and bhyve or init scripts may not be able to 
locate interface/disk names.

  Also, the vbox guest should be configured with a serial console.

> 3. if I can't boot it without conversion to something else, how do I go
> about it?
> 4. what's the maximum number of cpu and the maximum ram and HD space
> that I can give to a bhyve VM?

  bhyve's vCPU limit is 16. There are no limits on HD space.

> 5. if I make a VM and put opensuse (latest) on it, is it preferable to
> have the HD as raw or as ext-3 (or whatever the default for opensuse
> is)? If the latter, is there a penalty in terms of performance or
> security? The host runs zfs.

  Do you mean, the virtual disk type for the guest, something like 
vmdk/vdi/vhd/raw ?



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