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What I'm trying to do is:

wifiA(Int signal) <-wireless-> router A <-cable-> router B (AP) <-> Devices

problem is wifiA will vary, so I need router A to have a fixed IP for itself. Router B also needs fixed IP, cause I need to get in A setup to connect to other networks. If it has dinamyc IP it's hard to know what the ip is.

biggest problem is that since I will connect to different wifi's the subnet could be 192.168.1.XXX, 192.168.0.XXX, 192.168.5.XXX

so router A would be connected to a for example, while in the same time I need it to have an ip of for itself. How to do that?

also I am confused on how to configure both routers in the following fields:

Operation mode: bridge or NAT DHCP client, server, off subnet mask IP of each router (does it have to be in a range? I'm using for A and for B)

also, how should I interconnect both routers, in 1 to 4 router A linking to Internet port router B? or both in the 1-4 ports?

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Do you need to have multiple subnets? With this setup, you could have a single subnet by connecting all the devices by their LAN ports, and using a single DHCP server. This would be far simpler to manage. –  Paul Jul 10 '13 at 1:25
it's necessary to do so, because I interact with plenty of wifi signals, so one router would work as the horse, messing with all the IP translations, and the other is the one the devices will connect to so to receive internet signal and always keep their same ip's. another way to do it would be wireless repeater mode. it's ALMOST the same. but not the same. since I must connect to different wifi signals, the wireless repeater would be too much troble, cause all the devices connected would change their ip's when I connect to another wifi signal (which have a different DHCP server). –  FernandoSBS Jul 10 '13 at 1:29
Yeah I see. You really need to treat WifiA as your WAN so that its IP can change, but all the internal stuff can stay the same. This means unbridging the wifi from the LAN on wifiA. What make/model is it? –  Paul Jul 10 '13 at 1:36
it's a custom firmware, aprouter.com.br they have a demonstrative there so you can interact. Do you mean I should use NAT in router A? –  FernandoSBS Jul 10 '13 at 1:43
Yeah effectively. The wifi interface should be unbridged from the LAN ports if possible, and so anything on the LAN ports is internal, and the wifi gets whatever IP the wifi it is connecting to provides. Then you route from LAN to wifi and do NAT as if the wifi interface is your WAN interface. –  Paul Jul 10 '13 at 1:46

4 Answers 4

up vote 1 down vote accepted

As I see it you have router A connecting via wifi to the internet, and router B connecting via cable to router A, with some devices connecting either via cable or wifi to router b.

This kind of home router usually have three network interfaces:

  • 1 ethernet with an internal switch (you refer to them as ports 1-4)
  • 1 ethernet interface usually identified as WAN or Internet (you will not be using this one at all for your setup)
  • 1 802.11 interface (the wireless radio)

You should configure router A's wlan interface as being on the wan zone, its ethernet interface as being on the lan zone with an ip range outside the possible wan ranges.

Set lan with IP and modify dhcp server accordingly.

Wan gets assigned by DHCP when it associates with the internet ap. You do not need to care about your wan ip address.

On router B you don't have to do much. Asumming you start from default config and it's a home router, you simply assign it IP for lan and disable it's dhcp server.

The setup for router A is similar to this one

You will always connect to your router A using IP address, regardless of what network it's connected to on the wan side.

All of this is very easy to do if you can install openwrt or dd-wrt on both routers, or at least on router A.

EDIT: you mentioned your router doesn't support openwrt. Even if it does allow connecting to an AP as a client, you might be out of luck trying to route from ethernet lan to wlan with masquerading, never seen a home router that allowed this without changing the firmware.

Your options: get a new router (I have a few tp-link that work very well for this setup) or check if routerB supports openwrt and swap them.

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problem is I need DHCP on router B, so the devices gets their ip's. when you say do you mean to type in exactly like that or should I choose the end between 1 and 24? –  FernandoSBS Jul 10 '13 at 1:43
also, router A would be connecting as CLIENT, when you say to set it wan interface, how to configure like that? –  FernandoSBS Jul 10 '13 at 1:47
Again, you should install openwrt or dd-wrt on the router and follow the tutorial I linked. I don't know what make/model your router is, so can't tell if it's possible to install openwrt at all. means that you will set it's IP as and the network mask as You don't need dhcp on routerB, routerA will take care of it. –  gnp Jul 10 '13 at 2:15
It's not compatible aparently, mine uses RTL8186 chipset and is denominated "wap254g-e" or APR-WR254 –  FernandoSBS Jul 10 '13 at 12:12
Should I use NAT in router A or B? I don't want the router I connect my devices to to be using NAT, cause all the devices would receive the same IP and I don't like that. –  FernandoSBS Jul 10 '13 at 12:18

I think what your trying to do is this.

[Router A] <---WiFi---> [Router B] <---Ethernet---> [Router C]

It sounds like you are trying to extend Router A's range. And so you try to bridge it to Router C with Router B as a WiFi to Ethernet translator. BUT unless you want to spend HUNDREDS of $$$ on a repeater or router, Router B needs to go. There is OpenWRT, but that a whole other story.

Instead, Router B should be replaced as a computer of some sort with WiFi and Ethernet NICs. A Windows laptop is a suggestion. In Windows, you can bridge Router A's WiFi signal to the Ethernet port out to Router C.

Please give more details about the ENTIRE network so I can figure out your subnet and IP configuration issues. I'm not 100% sure what you mean. It sounds like a big network. If you did my method, this should be the result if you made the bridge transparent and both routers DHCP:

[Router A=\24] <--WiFi--> {Bridge} <--Ethernet--> {192.168.1.x [Router B=]}

Im still confused about your ip settings. More Info please!

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IP pre-A can be 192.168.1.X, 192.168.0.X, 10.0.0.X, anything like that. It will vary depending on what router I connect to get the wifi signal from. Router A I don't really care about what IP it uses. Router B must have a constant IP list so my devices work properly and I can name them. So a DHCP would work in the 192.168.1.X range. Please check the previous posts to understand the names I use for routers. –  FernandoSBS Jul 10 '13 at 12:14
can you check an answer that i've posted? –  FernandoSBS Jul 10 '13 at 19:57

First - are you trying to connect your cable modem to two routers? None will let you do that directly. If you manage to split your connection from the cable modem up using a switch, it still won't work. The cable modem is likely only going to recognize the first device it talks to, and only give a public IP to that.

Your question is confusing, but here is what I'm gathering what you want to do, and a diagram telling you what you need to do. With this, your network is flat, there is only one subnet (but two SSID's) and everything is pretty simple:

enter image description here

Yes, my MS paint diagrams are horrible. Also, if you can't disable DHCP and such on Router B, flash it to DD-WRT which lets you, or purchase another unit that does let you.

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no, not like your example. Router A is receiving internet signal by wifi from another router (this is the one that changes, since I can connect to different routers in this node. We could call the one sending wifi signal as "pre A router"). –  FernandoSBS Jul 10 '13 at 12:00
Gotcha. What you need to do is still similar. Connect one of Router B's LAN ports to a LAN port on Router A, and disable DHCP, DNS, and routing on Router B. It'll pull IP's and such from Router A. –  ultrasawblade Jul 10 '13 at 13:33
what about NAT? –  FernandoSBS Jul 10 '13 at 13:35
Basically on Router B, you don't want it to be a router, but a wireless bridge. So you want to configure Router B to NOT route, NOT do DHCP, and NOT do anything with regard to DNS. If you cannot disable routing on Router B, flash it to DD-WRT if possible, or simply leave the WAN port unconnected. At this point you can think of it as a switch with a wireless AP on top of it - things connected to it will get DHCP and Internet from Router A. Thus, you don't have to worry about NAT on router B, or different subnets at all. –  ultrasawblade Jul 10 '13 at 13:55

Ok so thanks to all the people who collaborated it's working perfectly. Final config is as follow:

Router A: NAT Enabled Wireless working as WAN DHCP on
Router B: Bridge DHCP off

Now I should open another thread for this question but since it involves all the configuration as explained in this thread I will shot it:

If I want to another AP be connected in CLIENT mode with router B, but I would like that it's traffic occur just between the 2, is it possible? It's a streaming device so I wouldn't like to overload Router A with it's traffic, since I don't need Internet access.

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You should open another question for this. Yes, it can be done. I don't see why you would need another AP connected in client mode to routerB, but it can be done in the same manner you configured routerA, except you will disable nat on this new router. –  gnp Jul 10 '13 at 21:51
Lets continue this on: superuser.com/questions/618200/… –  FernandoSBS Jul 10 '13 at 22:21
@gnp should I enable DHCP in "router c"? –  FernandoSBS Jul 11 '13 at 2:26

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