Is this (im)possibe to setup ?


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Hi everyone

I need a specific setup for my network, which I'm not sure if its possible to do

I'm using a DIR-615 router with latest dd-wrt sp2v24 installed on it , it works perfectly , I have a lot of settings on it so it controls everything, each client has a specific IP address linked to their mac address, WOL is enabled and lots of ports have been forwarded to each specific clients, what I'm tying to say is that this router is the primary router.

Now the problem is that we all are connected to this router through WLAN, which means not everyone gets a good signal and performance including myself, this router is connected to a virgin media cable modem, modem is on my room and the router is outside the room on the second floor (so that everyone in the flat can have a fair amount of signal) which is connected to the modem using a normal utp cable. Now what I'm thinking is that to connect another router to the modem and instead of sending the internet to the main router from the modem directly, give the internet to the main router using the second router, so the second router which is a Belkin router is getting internet from the modem directly and give it to the primary router so it can distribute it to everyone in the flat, so far so good,everything works , but the reason I want to do this is that I want to connect my own computer to this second router directly using wire, but the problem is that this router will give its own IP addresses from its DHCP to my PC, and I have no access to the primary router network and clients, and also I need to access my computer from outside the flat, which all related setting like port forwarding's have been done in the primary router but with this new configuration I cant even see the primary router from inside the network let alone I can access my computer from outside , I want to know if there is any solution to this network configuration,

What I need : The second router should provide internet to the primary router, in this case the primary router should rely on the second router for the internet connection and if any client (wifi or lan) has connected to the second router even though its connected directly to the modem the client has to get its IP from the primary router and it has to get the internet thourgh the primary router

I have attached the diagram of the network I would need to setup !

What I did so far :

I have set the subnets so they are the same

I have tried to disable DHCP on the second router , and tried to force my computer to get IP from primary router, but since it cant even ping the primary router so it cant get the IP

Im not sure if there is any setting in the routers to force them to use another routers DHCP for their clients !

Hope I have explained it clearly

Thanks for your help in advance

post-233402-0-61461200-1329361695_thumb.

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Is it possible with your setup to plug it like this instead?

Modem -> Primary router -> Secondary router.

This would probably work easier, especially with DD-WRT being your primary router...

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Interesting setup. I have done something similar myself, but there was one main difference. The Modem connected to the Primary router which had the DHCP server etc.., and then the Secondary router was fed internet from the Primary router. In order for computers connected to the Secondary to work, I had to disable DHCP on the secondary and connect the cable from the Primary router into one of the regular ports on the Secondary router (not the internet port). This was so the Secondary router acted just as a wireless/wired switch for the Primary router.

Modem -> Primary Router (DHCP) -> Secondary Router (no DHCP)

The secondary should then just act as a wireless/wired switch.

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You are right , that would be easy, but the problem is that it has to be first the secondary and then the primary, the reason is that the modem is in my room and Primary Router is on the second floor, so the Secondary Router has to be in my room connected to the modem so that I can connect my own PC to it using cable !

I cant move the primary to my room since it is the only router which supports 802.11 n (faster speed for everyone in the flat), it has to be in the middle of the floors !

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Is it possible with your setup to plug it like this instead?

Modem -> Primary router -> Secondary router.

This would probably work easier, especially with DD-WRT being your primary router...

Yeah, I also have to question the idea of connecting the modem to the "secondary" router. That doesn't seem to make much sense at all. As for the IP addresses, you could simply set the DHCP up on each router to the same subnet, but assigning a different range of IP addresses (for example, the first router might assign .10-.20 and the secondary might assign .21-.30, or something like that). Then everything on the network should see everything else with no problems.

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You are right , that would be easy, but the problem is that it has to be first the secondary and then the primary, the reason is that the modem is in my room and Primary Router is on the second floor, so the Secondary Router has to be in my room connected to the modem so that I can connect my own PC to it using cable !

I cant move the primary to my room since it is the only router which supports 802.11 n (faster speed for everyone in the flat), it has to be in the middle of the floors !

Then why don't you simply let the secondary be the primary, and vice versa? Again, it really doesn't make a lot of sense. No matter how you set it up, the one connected to your modem is still really going to be the primary router, since it will be the only device getting an IP address directly from the modem.

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You are right , that would be easy, but the problem is that it has to be first the secondary and then the primary, the reason is that the modem is in my room and Primary Router is on the second floor, so the Secondary Router has to be in my room connected to the modem so that I can connect my own PC to it using cable !

I cant move the primary to my room since it is the only router which supports 802.11 n (faster speed for everyone in the flat), it has to be in the middle of the floors !

Or you could run a new wire from the Primary to the Secondary, or if they are just 10/100 speed Ethernet ports you could split the wire since only 2 pair are used on 10/100. However, if you are using Gigabit (1000) then all 4 pairs are used in the cable. This is just a simple hack to avoid running new wires in difficult situations. Your best bet would be to switch up the order or do what roadwarrior said.

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I have a similar setup but it's a bit more like this:

http://www.redhax.com/media/RedHax.svg

Does your secondary router allow DHCP forwarding or VLANs?

In my case my "primary" router is a Windows box running TMG. I haven't been very lucky getting DHCP forwarding working but using VLANs I've routed the traffic the way I want.

Note in my case I've isolated the second network from the main one as I wanted a non-filtered network for my consoles when I have Xbox LAN parties going, however, it was more effort having the networks isolated than it would have been joining them.

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Yeah, I also have to question the idea of connecting the modem to the "secondary" router. That doesn't seem to make much sense at all. As for the IP addresses, you could simply set the DHCP up on each router to the same subnet, but assigning a different range of IP addresses (for example, the first router might assign .10-.20 and the secondary might assign .21-.30, or something like that). Then everything on the network should see everything else with no problems.

I do understand , it looks strange but I have all of my settings like access controls based on MAC address and IP addresses in the Primary Router, but I'll give it a try

Then why don't you simply let the secondary be the primary, and vice versa? Again, it really doesn't make a lot of sense. No matter how you set it up, the one connected to your modem is still really going to be the primary router, since it will be the only device getting an IP address directly from the modem.

Thats the best way actually ! I have ordered a new Mini PCI WLAN adapter for the Belkin router which is supported by DD-WRT as soon as I ge that I will install DD_WRT on it and try to make it as the primary one !

Or you could run a new wire from the Primary to the Secondary, or if they are just 10/100 speed Ethernet ports you could split the wire since only 2 pair are used on 10/100. However, if you are using Gigabit (1000) then all 4 pairs are used in the cable. This is just a simple hack to avoid running new wires in difficult situations. Your best bet would be to switch up the order or do what roadwarrior said.

Im trying not to use too much of cable ! :)

I have a similar setup but it's a bit more like this:

http://www.redhax.com/media/RedHax.svg

Does your secondary router allow DHCP forwarding or VLANs?

In my case my "primary" router is a Windows box running TMG. I haven't been very lucky getting DHCP forwarding working but using VLANs I've routed the traffic the way I want.

Note in my case I've isolated the second network from the main one as I wanted a non-filtered network for my consoles when I have Xbox LAN parties going, however, it was more effort having the networks isolated than it would have been joining them.

Looks interesting, Yes it'd support both if I install DD-WRT on it (I will as soon as I get my Mini PCI WLAN for it), shouldnt it work easily by just forwarding DHCP requests to the Primary router ? because I think DHCP forwarder is what exactly we need !

Thanks a lot everyone

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You would need a direct cable from the modem to the primary router. Then from the primary router you would have to run a cable back to the secondary router. Do not use the internet/wan port of the secondary router only use the switch ports. Disable dhcp on the secondary router and give it an ip address of 1 up from the primary router (192.168.x.1 primary router, 192.168.x.2 secondary router) and adjust the DHCP scope to give out addresses of 192.168.x.50-192.168.x.254.

This would be what you want and will work just fine. You may have to put in a inline coupler to have the wire go directly back to the primary router if the wire terminates where the secondary router is to make life a little easier for you.

http://www.google.co...ved=0CHQQ8wIwAA#

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^ exactly!

Your drawing does not show which ports your connected to on these routers. But I would have to guess your using the wan/internet ports on them and each one is natting.

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^ exactly!

Your drawing does not show which ports your connected to on these routers. But I would have to guess your using the wan/internet ports on them and each one is natting.

i agree, and double natting is never good
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I agree double natting should be avoided whenever possible - in those rare cases where its not. I would suggest you look again try and avoid it. But if there is no cost effective way of doing what you want to do without a double nat. Then it can work - you just need to understand that your doing it, and what that entails and what issues can come from it.

In his current drawing - if he has his second router natting.. Your not going to be able to use it to hand out dhcp to the devices connected 1st routers network.

Now what he could do is use is first router as the nat to the internet.. And then just use the second router as AccessPoint and use its dhcp server for all devices if he so desired. But he would have to set the dhcp to point to the first routers lan IP as the gateway.

But the 2nd router could be used as dhcp/dns

But if he wants to use it as access control to the internet, ie the gateway for all clients and what determines the ports that are forwarded to inside devices then it needs to be the device directly connected to the internet as sc302 pointed out already.

edit: vs using a coupler, I would just get a cable long enough to reach from modem to router you want to use as primary. Then as already stated just run another line back to 2nd router that you will just use as an accesspoint. What length of run are you talking from the modems location to the router you want to use as primary?

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If what Im trying to do works it means I dont need to have nat on the second router, it would be there just to pass the net connection to the Primary router and if there is any client connected to it, it would pass them to the dhcp forwarder to get the IP and also give them the internet through the primary router !

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The way you want it to work is the way I have described it to be setup in my above post.

If do it any other way, it will not work the way you want.

edit: I only suggested a coupler being that I don't know how the cables are currently ran, if they are behind walls, strung out in the open, or what have you. Only reason to use a coupler is if you can't or don't have the desire to run another cable from the cable modem to the primary router.

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Thanks for your reply

Your way means connecting Primary router to the modem which is the usual way and it always work perfectly , the thing is that I need the second router to be the first router connected to the modem !

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again, doing it any other way than the way I have described will not work.

You need to bypass the secondary router and go right to the primary router. Perhaps switching physical locations between primary and secondary routers, but to put it extremely simply without going into situations where it could work (if you had the proper equipment), you don't have a snow balls chance in firey hell for this to work with your setup.

For this to work in any way shape or form, the modem needs to connect directly

to the primary router...there are no ifs, ands, or buts about

this. Now you can have a switch between the primary router and cable

modem with nothing else connected except these two devices, you can make a vlan

on a switch (provided you have a managed switch) to connect these two devices

and have nothing else on that network, you can have a direct connection between

the two. Networking 101, you can only have 1 dhcp server on any

network. The cable modem by default is a dhcp server. This

causes a conflict and nothing will grab an IP, it is almost like having two pc's

with the same IP address...it confuses the network something fierce.

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"the thing is that I need the second router to be the first router connected to the modem !"

Well then its NOT going to work how you want it too.

If you want that 2nd router (primary in your picture) to do the nat and be the gateway/firewall for your network then it need to be connected to the modem.

Now you can leave it connected the way you have it, and use your 2nd router as dhcp and dns -- but its not going to be the gateway to the internet.

If you double nat there sure the 2nd router can be the gateway to the devices connected to it. But its not going to be able to hand out dhcp to the devices on its wan side. You could set it up as just a router if you wanted and then sure it could hand out dhcp to 2 different scopes. If your handing out only 1 scope then you would have to point to that first routers lan IP as the gateway because its the one connected to the internet.

I fail to comprehend why you can not just either join the wires you have now with the coupler sc302 suggested or run a new wire from the modem to the 2nd router. And then a wire back to your first and use it just as an accesspoint?

You want the 2nd router to be gateway/firewall off your network to the internet -- then it needs to be connected to the modem. Be it with 1 wire, or coupled wire or switch in between so that that 2nd router gets the public IP from the internet on its wan interface.

Or how about this -- if you like the capabilities of the 2nd router.. Buy another one and replace your first router with that one!! Then change the current 2nd router into just an accesspoint.

But you can not do what you want with the way your connecting it.

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Guys

I think you are right it seems there is no way to do it in my way ! I will install dd-wrt on the second router and make it primary ! thats the only thing I can do !

Thanks for your help

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