1

I have my main network 192.168.2.X and I placed a router running DD-WRT and placed machines under that router as 192.168.3.X. Is it possible to access those 192.168.3.X machines from the 192.168.2.X network or will I need to use a device that offers VPN support?

1
  • 2
    Why not run the second box as switch? Then all machines will be inside 192.168.2.x and no routing is necessary.
    – TJJ
    Jun 22, 2016 at 13:44

2 Answers 2

2

Yes, that's how routers work in the first place. On the first router, you need to add a route for 192.168.3.0/24 via the second router. I don't know how this translates to the thousand different fancy web UIs, but typically it'd look like this:

NETWORK       PREFIX (or NETMASK)         GATEWAY
-----------   -------------------------   -----------
192.168.3.0   /24    (or 255.255.255.0)   192.168.2.3

(Your second router will be 192.168.3.1 on the "inside" interface, but at the same time it will be 192.168.2.[something] on the "outside" interface. That's the one you should use as gateway.)

Also: If the second router performs NAT, ideally you should disable it – either completely (letting the first router NAT everything), or at least for your own subnets (although only advanced firewalls like iptables or pf support that). Double-NAT leads to confusion and headaches.

2
  • 2
    To expand on this a bit, what he is saying is that routers route packets between networks and by placing that configuration on the 192.168.2.x router, it tells it how to reach the 192.168.3.x router in order to route traffic there. NOTE: you may also need to add a route on the 192.168.3.x router pointing back to the first network.
    – MaQleod
    Jun 22, 2016 at 15:13
  • @MaQleod: The latter shouldn't be necessary – the automatically-added 'my subnet' route will already cover it. Jun 22, 2016 at 16:51
1

There is no need for a VPN in this case. You may have some routing to configure on 192.168.2.x. You may also need to configure forwarding on the DD-WRT router to ensure you are not masquerading traffic.

Devices on 192.168.2.x are likely routing to your main router. It likely won't know to send addresses in the 192.168.2.x range to the DD-WRT router. I expect the DD-WRT router has the WAN interface configured on 192.168.2.x. Add a route to 192.168.3.0/24 via the DD-WRT WAN IP address to any machines that need to reach the devices connected to DD-WRT.

If the machines connected to the DD-WRT are only connecting to other servers you should be fine without any additional setup.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .