Question Help please with setting up second router

[rubsley]

Hi all, I'm looking to set up a router extension and I'm not having much luck.

Router A feeds Router B through ethernet. They're set up on different channels. Router A has one broadcast name and a password, Router B has another network name and is open.

Guides I've read seem fairly straightforward: turn off DHCP on Router B, change the IP address, and off you go. Some of them mention something about a 'Gateway' setting (or NAT) but I'm not sure what that means.

When I just connect them without doing much, they work, but the internet drops in and out. I can turn off DHCP on Router B no problem. And I can change the IP address - but once I do that, the internet disappears and I can no longer access the router (by inputting the new address - or the old one, for that matter).

The default on both is 192.168.1.1 (subnet 255.255.255.0).

Any help! I'm about ready to start pulling some hair out.

Cheers.

 

[rubsley]

PS I'm using it RIGHT NOW, having changed no settings - DHCP still on on Router B; IP addresses still the same - and I guess it'll come in and out. But would love to get this thing straight. It seems like it should be easy. But none of the guides and instructions seem to have put it right so far.

 

[jojesa]

Could you provide the devices model.
If router B will be permanently connected via Ethernet to router A then (besides turning off DHCP and changing the default IP) it should be setup as an access point.
After setting up router B, the Ethernet cable should be connected to one of the 4 LAN port on router A and into the main Ethernet port (LAN port) on router B.

 

[rubsley]

Thanks. That's basically how it is setup - but, as above, I'm not able to change the default IP (or rather, I can change it, but then the internet and access stops working).

Router A is a Technicolor TG799TSVN and Router B is an Asus DSL-N55U.

Does "setting it up as an access point" require anything further?

Appreciate the help!

 

[bill001g]

If it has a AP mode then the software does most the work for you. Otherwise the method is Cable lan-lan, disable dhcp, change lan ip (use 192.168.1.250 for example).

Be aware having the network open on the second router allows people to have access to devices connected to your main router. You need a much more advanced design to setup a open network that is secure. I would never use a open network you never know when the idiot kids from down the street decide to do something bad on it.

 

[rubsley]

Thanks. I hear ya on open networks - but we're all good, there aren't any idiot kids down the street.

(It's actually for a yoga retreat centre: Router A is in the owners' house; Router B in communal library where everyone can access. They're all good sorts here. )

Any feedback on the IP changing issues I'm having? I tried 192.168.1.2, x.x.2.1, and x.x.15.1, and none of those would let me access afterwards. I'll try your suggestion next - though I'm thinking it shouldn't be about that, right?

Is there maybe something I need to do on my laptop, to get it to reconnect after the change?

 

[bill001g]

When you run it as a AP the ip is only used for management. It is the same as a pc or printer on the network it is a end device.

 

[rubsley]

So how do I run it as an AP? Or am I doing that already just by connecting them LAN-LAN?

(At the minute, DHCP isn't disabled and the IP address for both routers is the same - and it seems to be working, though will probably stop working again at some point.)

 

[bill001g]

Cabling it lan-lan is the first step to a AP. The traffic does not pass through the router part of the cpu. The lan ports are a small switch and they connect internally to the wifi chips.

The DHCP server function only is used when machines first obtain a IP address but having 2 on the network you will get random results if a machine requests a IP. It is basically a race condition as to which dhcp server responds first. The duplicate IP is a much worse problem. The machines for a short period of time will keep the mac address associated with the first router mapped to that IP. After a period of time though they will issue a ARP command to renew the mapping. This again gives random results and it will work if you get lucky and the main router responds first.

 

[rubsley]

Good to know, and it explains the on-off nature of the connection.

So what's the solution to the trying to change the IP on Router B problem?

Here are a couple of screenshots from Router B:

For some reason, it's not letting me change the language to English at the moment; but hopefully that second one is clear enough (I took the first one earlier).

Funny how these things can be so temporamental.

 

[rubsley]

One other thing: when I'm connected to Router B, normally when I got to 192.168.1.1 I get the setup page for Router A; but just now I got Router B for the first time (back to Router A now).

Don't know if that helps anyone with the diagnosis.

Cheers.

 

[bill001g]

I can be tricky to change the IP address while you are on a network. The normal method is to connect to the router directly with it disconnected from everything else. You want to change the IP address first and then disable the DHCP. It maybe a little tricky to do now that you have disabled the DHCP. You will likely have to manually set a ip address on your PC.

The routers are actually pretty smart you reset the IP and in theory you should lose connectivity since the ip has changed. They will force the browser to load the new ip address just before it changes the IP. What is even more surprising is you can change the network completely say to 10.10.10.1 and the dhcp service will give you a new ip and somehow redirect you. I never looked into how this was being done but it may have something to do with being directly connected.

 

[rubsley]

Thanks for that.

So at the minute, DHCP isn't disabled. All the guides I read say to do this first, and then changing the IP (if necessary) - but you suggest it's better to do it the other way around?

 

[rubsley]

What about if I change the IP on Router A, since Router B doesn't seem to be complying? Any suggestions on that idea? For example, is it a good idea? What would I change it to, and the range?

 

[bill001g]

That will work but is not real common. It could be confusing since most people assume the 192.168.1.1 ip is the gateway.

Technically you can use any ip but the other common one people use if they do not use .1 is to use 192.168.1.254. It should work fine and the DHCP server should give out this ip to the end stations.

 

[rubsley]

Who would it be confusing to?

If I set it to 192.168.1.254 would I have to alter the IP range?

 

[bill001g]

Maybe nobody since you understand it but for example you would have to explain it if you asked a question here since it is not the common way.

The reason 254 is chosen is it is the top usable address in the subnet. If you mean the DHCP range it depends what the default is. It would be best to exclude it but in a small network it likely does not matter DHCP gives the IP out from the bottom of the range and it is unlikely to hit the top.