bridge firewall in virtualbox not passing traffic after upgrade to stable/9

[Peter]

> Hello,
>   Was running 8.2 and virtualbox 3 - wiped Freebsd 8.2, installed 9.0,
> installed latest virtualbox port 4.0.14 and the networking broke in my
> vms.
>
> Setup I had:
>
> {vm1,vm2,etc}---> vbox internal network -> em2[firewall VM]em1 -->
> re0[physical box]-->ISP
>
> the firewall vm has this:
> ifconfig_em0='172.20.6.210/24'
> cloned_interfaces="bridge0"
> ifconfig_bridge0="addm em1 addm em2 up"
> ifconfig_em1="up"
> ifconfig_em2="up"
>
> Firewall vm has this setup:
> nic1 - bridge re0
> nic2 - bridge re0
> nic3 - internal network
>
> The VMs are still on 8.2, the only change was virtualbox from 3 to 4.0.14
> and host system fresh install of stable/9.
>
> vboxnet is loaded, if I change the VMs to just bridge re0, they are able
> to get out, if I put them on the internal network, nothing gets out.
>
> internal networking works because without bridge and just setting static
> IP on vm1 and firewall vm em2, they talk without problem.
>
> ]Peter[
>   it can't be this hard.
>
Just a follow up with more info.

Set 2 vms and booting from 9 release cd using live system option.
Host system is stable/9, vbox 4.0.14:
Per the handbook setup bridging on firewall_vm that has no IP, and only
two interfaces [em0 - external, and em1 - internal networking]
http://www.freebsd.org/doc/handbook/network-bridging.html

On client_vm, em0 is connected to internal network and should pass through
that bridge, but I get nothing:

client_vm -> internal network -> em1[bridge vm]em0 -> internet

]Peter[
  on bridge vm, doing dhclient bridge0 gets nothing, doing dhclient em0
gets IP....