VirtualBox: No network connectivity. Weird vboxnetflt.ko/vboxnetadp.ko behaviour

Norbert Papke npapke at
Fri Nov 27 16:36:16 UTC 2009

On November 27, 2009, O. Hartmann wrote:
> Befor going deeper into my config I will report some strange behaviour
> of needed kernel modules
> vboxnetflt.ko
> vboxnetadp.ko
> Both are needed for networking on VirtualBox and they get loaded at
> startup vi /boot/loader.conf. But to have a working network, I have to
> unload and then reload them, since if they get loaded at startup,
> networking is broken in virtual box!

The vboxnetadp.ko is needed for the "host-only adapter" mode, I tend not to 
load it. For bridged mode, you need vboxnetflt.ko.

I have been having good luck by always loading vboxnetadp.ko manually rather 
than from loader.conf.

> My FreeBSD-based config is simple. I have a bridged NIC (msk0), a tap0
> device which is member of the bridge.

I do not use a tap device. It should not be needed.  I bridge the physical 
device directly.

> Has anybody similar trouble?

The modules are a somewhat temperamental.  When I follow the above, it works 
great.  When I deviate, I sometimes have trouble.


-- Norbert Papke.
   npapke at
Protecting your Internet's level playing field

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