How does it work - ethernet - vlan - bridge - tap flow


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Messages: 1

Hello! I need some help with understanding some base things.
I have FreeBSD virtual machine on Windows host with VirtualBox. At FreeBSD machine running OpenVPN client with Tap confuguratin (cant use Tun for some reasons).
interfaces: em0 - external connection and local network with host PC
tap0 - OpenVPN
bridge0 - tap/vlan inteface
Vlan1 - network for OpenVPN machines

OpenVPN work perfectly from FreeBSD machine

I want use FreeBSD as gateway for PC Windows 7 host machine.
1. Add route at Windows Host to FreeBSD em0 IF
2. Turnd on forwarding on FreeBSD/enabled gateway

Help me please understand packet flow from windows host through em0 - tap0 interfaces. How does it work?

default UGS em0 link#4 U vlan1 link#4 UHS lo0 link#3 U tap0

If i ping from win host, i can cee incoming traffic in Tcpdump -i em0, also in Tcpdump -i tap0, but nothing at Tcpdump -i Vlan1. Why? How does it work? i didnt see route via tap0. I thought it should be "em0 - vlan1 - bridge0 - tap0" but it work like "em0 - tap0" without "- valn- bridge -"

Seems i didnt understand some basics with bridging but cant find answers.

I am newbie at FreeBSD. Manuals didnt get answer to me (may be i cant find answer because of my bad english). SO i will be
appreciate for any help.