View Full Version : SB3 can not connect to 2nd router when using 2 routers

2009-01-04, 08:04
Hi - I have a (not very good) SpeedTouch router which my ISP requires me to use. I hook a LinkSys WRT54GX into the SppedTouch via the NET socket. Both routers have the same WEP key. On the secondary LinkSys router I set "Internet connection type" to "Auto config DHCP" and I also disable "DHCP Server" since I gather the SpeedTouch will perform this task.

This all works fine. My wireless laptop connects to the LinkSys, and my main desktop and a network drive that are wired into the LinkSys work.

However the SB3 will only connect to the SpeedTouch. When I try to connect to the LinkSys all works until I select "Obtain IP address automatically" on the SB3. It then looks for one and finally says "Couldn't find DHCP server" and "Go right to self-assign an IP address". Not sure what to do here, but it also seems very odd that my laptop happily connects to the LinkSys.

Any idea what is goiing on here and how to remedy it?

2009-01-04, 08:31
Don't quite understand your wiring.

What is the "net" socket.

And where are you plugging the other end of that wire into the linksys.

The correct way to use a router (linksys) as an access-point and switch is to.

1. Give it an address on the network implemented by the router that is different from the router and NOT in the router DHCP range. xxx.xxx.xxx.2 is a standard choice.

2. Turn off DHCP.

3. Set its wireless config the same as the router - with either the same or a different channel. I use different channel.

4. Connect an ether net wire from one of the lan ports on the router to one of the lan ports on the AP. The AP Wan port MUST NOT BE USED.

You should be able to reach the config pages of the AP by using the address you gave it during the set up.

2009-01-04, 08:50
Many thanks for your help.
I just looked again and I think that what you suggest is exactly what I have done. Ignore my "NET socket" comment - I have taken an ethernet wire from a LAN socket on one router to a LAN socket on the other router. The addresses of the two routers are (Speedtouch) and (linksys). DHCP Server is disabled. The setup must be pretty much correct since my laptop connects wirelesly without any trouble. On the otherhand the SB3 connects to the LinkSys but fails to get the IP address as explained in my original post - that is the problem. Any ideas?

2009-01-04, 13:45
If you have control over the speedtouch router's address, change it to the more standard I have some vague memories about issues with high addresses - not specifically SB3 but just stuff.

2009-01-04, 15:26
thanks again - I have had a good look in the speedtouch configuration menus but can't see anything that enables me to do that (although it seems easy enough on the LinkSys)

Mick Seymour
2009-01-05, 01:58
My setup is very similar and is working with a Zyxel ISP provided broadband router and Linksys WRT54GS. My music server is hard wired to the Linksys and the SB3 is connected to it via wireless. The Zyxel wireless runs on a different channel and as yours, has the same security settings except for SSID.

Your Linksys Basic setup sounds correct; Auto Configuration - DHCP, Local IP Address set, DHCP disabled. On the Setup, Advanced Routing tab, my Operating Mode is set to Router as detailed in the Linksys documentation. Check yours is.

On my Zyxel, it has the usual ISP type settings for obtaining an IP address and DNS from the ISP and DHCP is enabled.

The local IP address of the SpeedTouch shouldn't matter so longs as it is in the same network range as the Linksys. Yours is. Check that the Subnet Mask is set the same on both, usually for a standard class C range although your ISP may be using subnetting.

Make sure the addessess in the DHCP range are not clashing with any non DHCP connected machines.

The other thing to check is whether you have MAC filtering turned on for wireless connections on the Linksys or SpeedTouch. If so, make sure you have the SB MAC in the list.

2009-01-05, 14:21
Many thanks - sounds like we have near identical setups with the difference that yours works!

Regarding my LinkSys -> Setup -> Advanced Routing tab, I can not see an Operating Mode (or anywhere else for that matter). There is a "Nat mode" which is Enabled. It says in the help that this should be disabled if there is another router present, but I tried this and it made no difference.

The Subnet Mask is on the LinkSys, but I can not see this anywere on the SpeedTouch.

MAC Filtering is turned off.

On the LinkSys the DHCP server is turned off so does it make sense to have an address range? All this is greyed out in the menu.

The puzzling thing is that my Vista laptop connects very happily to the LinkSys.

On another note, is it best to select Automatic channel selection, or to try and find a channel that works and stick with it. I live in a flat in London surrounded by wireless connections!

Mick Seymour
2009-01-06, 02:14
So everything else wireless and wired connects to the Linksys and works, getting IP addresses and DNS from DHCP on the SpeedTouch. Ok.

Test moving the SB3 so you can connect wired to the Linksys. Can it see the DHCP server then? If so, that narrows the problem to a wireless one.

Once it connects wired, turn off the SB3, disconnect it and with it sitting close to the Linksys set it up for wireless again. Can it see the DHCP server now? If so, it may be signal strength causing the problem. If not, I'd suspect channel interference.

I set different channels on my routers explicitly.

Just a thought. have you set different SSIDs on the routers?

2009-01-06, 14:55
Good idea! i tried it and the SB3 did connect via a wired connect using an IP address of I tried doing it wirelessly and manually selecting this IP address and it seemed to connect to the network but then failed to connect to the SqueezeCenter. So this was better but still not quite there.

I do use different SSIDs. I get a strong signal (they are only 15 feet apart) but I think there is a lot of interference around, especially over weekends when the scrolling display gets very jerky.

On another note I contacted my ISP and they have changed their tune - it appears I can do without the SpeedTouch altogether so when I get a moment I will see if that route works. I don't see there being much advantage to having two routers.

2009-01-06, 15:00
Try one SSID for both. That's the standard multi-access point approach.

2009-01-06, 15:49
I do the same thing. If they're connected via a cable (which you say they are) then why do you bother about the SSID on the SpeedTouch - just turn wireless off on this altogether. That will make things much simpler as there will be only one possible router to which devices can connect.

2009-01-07, 14:25
You have two instances of NAT (Network Address Translation) going. One on the speedtouch and one on the linksys. Decide what device you want to use as a firewall and what device you want to use for wireless. My suggestion is to get into the config on the speedtouch and disable the wireless. If there is an option to turn off the firewall on the speedtouch and just use it as an access device do that and use the linksys for firewalling and wireless. Then on the linksys it should obtain an IP address through DHCP. Turn on it's DHCP server and then plug all computers into it (or connect wirelessly to it). Set all computers to get IP addresses through DHCP.

If I could upload a Visio diagram it would make this explanation much easier.