GNS3 – How to Connect GNS3 to Real Network

There are several ways you can approach this:

• Don't use a NAT adapter. I realize this may not be possible/desirable, but if you can select "Bridged" adapter and get an IP from that same subnet, all these problems (both gust->host and host->guest) go away.

• Use two virtual adapters, the regular NAT one for internet access, and a second "loopback" adapter in bridged mode on your own private subnet. The loopback will be used for communication between the host and guest(s), while the NAT adapter will handle the traffic outside of the host.

• There are a number of tricks to do port forwarding to the hosts, as well as open up guests to see the host. By default, I believe, both of these are blocked as to provide a better sandbox. There are plenty of questions here on Server Fault (tagged with VirtualBox) that talk about punching holes as described.

Hmm, sorry to double post too, but I believe the StackOverflow one may be redirected or deleted (as not appropriate for that site).

Here are my questions again (can't put it in a simple comment):

This is weird: the router should be the one with enough dedicated interface to separate all your lans as needed and route between them.

From the picture it's as if your server (3.50) has 2 interfaces, one in 3.x, the other in 2.x. This should mean that between it and the PCs, there is another device (a switch? hub? another router?) so that they can talk together.

Please update the picture to give all the interfaces you use on each device (router, and server, especially) so we can clearly see what you need to do.

from the picture I can guess:

• the router you show is the Wifi router.
• the laptop and the server both connect to it via WiFi.

But I can't guess:

• how does the server and the PCs connect together? via another switch? via the LAN port of the router? The fact you can't route between them seems to indicate they are not on the same lan at all...