router behind router?

Discussion in 'Networking Issues' started by kardasan, Nov 6, 2005.

  1. kardasan

    kardasan Network Guru Member

    I have bought WRT54GC router to make use of my home internet connection and divide it between 2 wired PCs and 2 wireless laptops. First of all i'm a real noob in networking, so i bet that i'm doing something wrong or i've missed some information somewhere.
    Anyway, My network looks like this:
    ISP Connection ---> ROUTER 1-----> LAN NETWORK
                                                             |-----> WRT54GC ----> My home Network
    before i had this router i was connecting to the LAN by the static IP. After I connected my ethernet cable to the router's Internet port, the "Internet" light stayed dark. I've tried to use crossover, still nothing. I've tried to connect my PC to the router's internet port, light went up. So the port is good, or at least it gets something. Anyway i couldn't get the whole router to work. I can connect to it when i'm plugged into one of it's ethernet ports, I can ping it, but when I go into administration tab in the web-interface i can't ping anything outside, of course i can't access internet, nor the rest of the LAN. I've tried to set the router to DHCP, nothing, to static IP (with settings as if I would have connected my PC to the network) nothing, nothing comes outside.
    Any help? Any Ideas? What am I doing wrong?

    Thanks in advance
  2. howardp6

    howardp6 Network Guru Member

    To connect your WRT54GC router to the other router you have to set it up. First disable the DHCP server and if the default local IP Address of conflicts with the other router change it. bit stay in the same subnet. Assign it an address the is outside the range of the of DHCP server on the router and save the setting. On the advanced routing. set it as arouter and not a gateway and save your setting. Powetr it down and connect one of the LAN ports to one of LAN ports on you router not the WAN port. If you are using static address, make certain you enter the Local IP Address of your origian reouter as the gateway and the addresses of the DNS servers from your ISP and save your setting.
  3. kardasan

    kardasan Network Guru Member

    ok that works but it's not exacltly what i wanted to do. I wanted to make my home network a subnet of the whole LAN network, so i could use DHCP in it without enabling it in the main router (so that my home network will be seen only as one IP from the outside). Is it possible?
  4. howardp6

    howardp6 Network Guru Member

    With NAT your computers on computer behind the router are not visible to the internet. Enable the DHCP server and issue addresses in sthe 192.168.1.X range ot with a 10.X.X.X range, which are private addresses, which are not visable from the internet.
  5. kardasan

    kardasan Network Guru Member

    ok call me a moron, but i don't get it :(
    That's the first time for me to configure such thing.
    As far as I understand, I have to set up NAT on my WRT54gc router. What i don't quite understand is:
    Now let's say that the connection settings I was using to connect to the network provided by ROUTER 1 (name from the diagram in first post) was like this:

    how to set up wrt54gc to be seen as by the ROUTER 1 and to divide this connection between it's clients? That's the purpose of NAT, isn't it?

    Sorry for my ignorance ;-)
  6. DocLarge

    DocLarge Super Moderator Staff Member Member

    You're not "exactly" using a router that requires configuration of NAT unless you've been playing around with sveasoft or something like that. Otherwise, NAT is already configured for you; your concern is just "getting out." So, let's look at two scenarios using the numbers you posted above.

    <u>Scenario 1</u>

    If you just want to use the same IP scheme already established by Router 1 (, then all you have to do is configure your WRT54GC to work "as an access point" (which is the direction Howard was going in). Here's the difference:

    "TURN OFF" DHCP on your main router (yes, I went there :) ) Run "straight thru" CAT 5 from one of Router 1's LAN ports to one of the 4 LAN ports on the WRT54GC; however, before you run the cable between the two, log into the WRT54GC and give it an IP address consistent with Router 1's ip scheme ( Next, configure the DHCP "ON THE WRT54GC" to give out "ONLY" enough IP's to correspond with the number of systems you'll have on your private LAN. Then, go to the "wireless" section set your channel to either 1, 6, or 11 (there's no overlap with any of these).

    Make sure you "disable" the ssid; as long as your encryption and ip schemes of your wireless cards on your computers match the WRT54GC, you'll be able to communicate with it; choose WPA2 on the WRT54GC provided your wireless cards support it, if not, use the highest level of encryption you have available.

    You should now have all your private computers utilizing the existing connection of your perimeter router (router 1) via your WRT54GC. I'm running both of these scenarios at home, by the way, so I know it will work :)

    <u>Scenario 2</u>

    Use this configuration if you want to have a "separate subnet" available to "F" around on "and still be able to connect to the internet via Router 1:"

    Run "straigth thru" CAT5 from one the Router 1's LAN ports to the WAN port of the WRT54GC. Enable DHCP on Router 1 to give out "ONE" ip address for the WRT54GC to pull. Just like before, you'll log into the WRT54GC prior to running the cable; this time you'll need to give it a "DIFFERENT" ip scheme so as not to conflict with Router 1's subnet (try After you run the cable, the WRT54GC's WAN port is now on the same ip segment as Router 1 ( which will give you internet access. Again, if you want your computers to only get their ip's from the WRT54GC, "ONLY" configure enough IP's to correspond with the number of systems you'll have on your private LAN.

    Give it a whirl...

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice