Bridged networking does not work on em0 / 8.0

[Tobias Grosser]

Hi,

I am trying to use VirtualBox since a while, however bridged networking
never worked, even it is supposed to do so.

My Host is: FreeBSD 8.0 / RELENG, 32bit, em0 ethernet

I use a Knoppix LiveCD as a guest OS (also tried with debian and
Windows)

When I try to get an IP using DHCP the request is sent out to my router
and is returned to my freebsd host.

tcpdump on em0 on the FreeBSD host:

11:30:35.614121 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP,
Request from 08:00:27:25:17:97 (oui Unknown), length 300
11:30:35.614131 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP,
Request from 08:00:27:25:17:97 (oui Unknown), length 300
11:30:36.621477 IP fritz.box.bootps > 255.255.255.255.bootpc:
BOOTP/DHCP, Reply, length 548

However it never appears back at my linux guest

tcpdump on eth0 on the linux guest:

11:30:34.008830 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP,
Request from 08:00:27:25:17:97 (oui Unknown), length 300
11:30:43.004510 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP,
Request from 08:00:27:25:17:97 (oui Unknown), length 300
11:30:58.015919 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP,
Request from 08:00:27:25:17:97 (oui Unknown), length 300

There seems also to be some kind of packet duplication, as the packet
sent at 11:30:34 appears twice in the tcpdump of the FreeBSD host.

Any ideas how to debug this?

Tobias