Hi,
Ok, I am managing a classroom LAB environment. Each student has a bunch of VMs running in Hyper-V and some physical devices on their desk. Each student has a switch on their desk which is, in turn, connected to a central switch using a vLAN to separate each environment. Overall, the environment consists of 3 subnets and a central virtual router which was running dd-wrt, but which I have just moved to OpenWRT. All environments are identical.
The router has 4 interfaces....
- A WAN interface which connects to a common (shared) backbone for internet access. Configured with NAT
- A LAN interface with half a dozen or so machines. This is the 192.168.1.0 Class C Network.
- A LAN interface with another two or three machines (representing a simulated remote site). This is the 192.168.2.0 Class C Network.
- A LAN interface to the vLAN which ultimately connects to the desktop. This is the 192.168.3.0 Class C Network.
The Windows DC (which is also the DNS and DHCP server) is on the 192.168.1.0 network, The router is configured to forward DHCP requests.
Ok, all this work and is exactly how we need it!
BUT!
I have been tasked with making the physical machines remote. The idea is that we will be able to host the Hyper-V environment in a data-center and therefore not need to transport as much equipment when providing travelling classes.
So, my plan is to run OpenVPN (server) on the router and the client on a Windows box. This box will have two NICs, one that connects to the internet and can therefor run the VPN and the other which will connect to the desktop switch for the other physical machines.
So far, so good!
The thing is, I HAVE to have the DHCP server on the 192.168.1.0 network, so I need to have the DHCP forwarding going over the VPN. I've looked at both tunneling and bridging, but have hit a series of roadblocks in each case...
If I go for a Tunnel, then the OpenWRT router and the desktop machine act as a pair of routers. This is great, but I don't think I can then have a DHCP relay to pass the requests to the central server.
If I go for a Bridge, then, if I understand it correctly, the desktop machine will "see" itself as being on the remote LAN. But if I do this, the 192.168.3.0 network doesn't actually exist on the back end, so what do I Bridge the TAP interface with? Also, as soon as I try this, the connection fails! With TUN, I have set up a CA etc and all is well, but as soon as I try to switch to TAP, I get errors complaining about TLS!
So, can anyone help me achieve what I'm after? the physical machine is currently running Windoze, but if I need to change that to a flavour of Linux (or even another OpenWRT) that can be done.
I will be cross posting this in the OpenWRT forums (I hope that doesn't violate the forum rules). As always with these things, I need a fairly rapid turn-around!
Any and all help greatly appreciated, however please don't suggest putting DHCP somewhere else, that is a fixed point!
TIA
