Where to find some good examples for TCP/IP Routing

Question

I got an wireless access point (zyxel g-1000) and connected it to my home-network. But now i would drive this traffic in annother ip-range (172.16.1.x) than my regular network to restrict the access to the resources. Not all resources should be blocked and there comes my question to play: I have a web based wiki running on a particular ip (e.g. 192.168.1.100) which should be accessible from the 172.16.1.x net.

a cute route on my gateway (192.168.1.1) should do the job, is this possible?

Update:

Thanks for the given answers. But i would like to do the magic on my gateway-pc.

i define on gateway's eth1 an second IP

ifconfig  eth1:1 172.16.1.1

Now the job is to route on eth1 and eth1:1 so that the 192.168.1.100 is seen on the 172.168.1.x side.

Is this more a network programming issue?

Answer 1

If this is the same server as on your other question, see Step 1 of my answer there to setup your alias eth1:1 to startup on boot. I think that's all you need to do.

Once that's done, your routing table should look something like this:

$ /sbin/route
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
192.168.1.0     *               255.255.255.0   U     0      0        0 eth1
172.16.1.0      *               255.255.255.0   U     0      0        0 eth1
default         xx.xx.xx.xx     0.0.0.0         UG    0      0        0 eth0

Note that both your LAN subnets route to eth1; that's OK -- that's only the physical interface used. This should be all you need.

Answer 2

I think an elegant solution would be along these lines.

• Alias 1 172.16.1.x IP address on the Wiki machine with IP 192.168.1.100
  (this way its in the restricted network too).
• Additionally, setup firewall rules on that machine to restrict services other than the Wiki (port 80?) for this aliased network

Answer 3

I tried to find some documentation for a G-1000 ZyXel product but came up blank.

I would expect that the access point will support having a separate subnet for the the wireless clients. If so, then it will take care of the routing between the wired and wireless lans.

Once you have the networks configured then block everything from accessing wired networks and setup exceptions for the service you wish to allow - like your wiki server and possibly the internet gateway if it is not the access point.