pomtom44: Thats exactly what I said isnt it?
I want to run in TAP mode so the traffic on the LAN uses the Clients IP, so then I can use my current firewall to do my traffic management
Like I do for my current vlans and devices.
I can't do that on TUN mode as my firewall only sees the internal IP of my VPN server and not the client IP thats connecting.
The firewall will see the IP addresses allocated in TUN mode so you can apply traffic management. It is just that the traffic will come from a different subnet rather than your current LAN subnet.
So in TAP mode you would have
Firewall 192.168.1.1 + Subnet 192.168.1.0/24 + OpenVPN Server on 192.168.1.2 and LAN IP addresses of 192.168.1.10-50 and VPN IP addresses 192.168.1.200-192.168.1.210
Or something like that. The issue is the client to dish out the IPs is a lot more complicated
In TUN mode you would have:
Firewall 192.168.1.1 + Subnet 192.168.1.0/24 + OpenVPN Server on 192.168.1.2 and LAN IP addresses of 192.168.1.10-50
Then you would also have a network route on the Firewall for 192.168.2.0/24 via 192.168.1.2
OpenVPN would have the TUN interface on 192.168.2.1 and hand out IP Addresses on 192.168.2.10-50 or whatever and you would run Avahi on the OpenVPN Server as it would be a router.
Then the firewall would need to apply policy to 192.168.1.0/24 and 192.168.2.0/24 based on the traffic management you require.
This is what I have currently
Internet ---> Router/Firewall ---> 192.168.10.0 network ---> 192.168.10.10 (VPN Server)
If I run in TUN mode I have my OpenVPN server set to hand out 192.168.10.100-200
The traffic I see on my router/firewall all comes from 192.168.10.10 due to the routing happening on the OpenVPN server.
I connect my phone, It gets 192.168.10.101,
I browse the web, my firewall sees the traffic from 10.10 not 10.101
So I can't put client level filtering in place on the firewall.