vooteleaer
Hello
This is my first post here, so be gentle with me 😃
The situation is as follows:
Ubuntu 16.x running openvpn server. tun0 device bridged with eth0 to br0, 192.168.1.x address space shared with local network.
Several clients connecting via tun0. Let's say some windows machines, some macs. All of those are OK. They get their 192.168.1.x free address and so on.
Except one raspberry, which is the key ingredient in this project.
It uses 4G dongle which acts as eth0, has address 192.168.8.100 in raspbian, also tap0 with normal 192.168.1.x address assigned by server.
So far, so good, except - raspberry has to connect my custom server application, which also has to talk back to raspberry. This application sees raspberry as 192.168.8.100 somehow. Obviously it tries to send stuff back to this address, which of course doesn't exist in VPN.
How on hell the other adapter's IP address gets through vpn?
vooteleaer
tcpdump indeed shows udp packets from 192.168.8.100
01:48:19.791704 IP 192.168.8.100.34227 > 192.168.1.2.14550: UDP, length 36
01:48:19.791771 IP 192.168.8.100.34227 > 192.168.1.2.14550: UDP, length 48
01:48:19.791822 IP 192.168.8.100.34227 > 192.168.1.2.14550: UDP, length 28
and so on
