Can't access ADSL via Senao bridge.

[Woofda]

Hi.

I've recently set up a wireless brige (Senao SL-3054CB3 PLUS Deluxe on both sides) to link my home LAN to my friend's (his house is just down the road from mine).

He has Telkom ADSL (the 512 Business package) at his house, using a Netgear DG834GUK to access it (combined ADSL modem/router/switch/802.11g).

He has no problem using ADSL from a Windows machine at his place. The Senao on his side of the wireless bridge is plugged into one of the ethernet ports on the Netgear modem/router, just like the machine that is able to access ADSL.

Here's the problem:

From my place (i.e. over the bridge to his place), I can't access sites outside of our 2 LANS via ADSL. I've set my gateway to be the Netgear ADSL modem at his place. I can ping that IP. I can even ping the IP that is assigned to the Netgear ADSL modem by Telkom. However, when I try to ping the IP of the gateway on the Telkom side of the link, I get no reponse. With exactly the same setup as me, my friend has no problems pinging that IP and accessing sites outside of our LANs.

The firewall settings on the Netgear allow all outgoing connections for all IPs.

Is Telkom somehow detecting that I'm coming in over a wireless bridge and blocking access from my LAN? NAT is set on the Netgear ADSL modem, so this seems strange to me. Surely trafffic from machines on my LAN should look the same as traffic from machines on my friend's LAN to Telkom?

Thanks for any help with this problem.

Woofda

 

[DFantom]

I've recently set up a wireless brige (Senao SL-3054CB3 PLUS Deluxe on both sides) to link my home LAN to my friend's (his house is just down the road from mine).

*cough*illegal*cough*

From my place (i.e. over the bridge to his place), I can't access sites outside of our 2 LANS via ADSL.

I would guess firewall isn't allowing forwarding of packets etc.. in the setup. Try disabling the firewall and seeing if that helps. Otherwise check that masquerading or natting is setup correctly.

Is Telkom somehow detecting that I'm coming in over a wireless bridge and blocking access from my LAN?

Highly doubt it, if they are then it's very impressive. In fact I would go as far as to say they couldn't tell.

 

[rsachoc]

Woodfa

Maybe its DNS issues?

Try this to test:

1) From your friends amchine, go to a command prompt, and type ping www.is.co.za
2) It will bring up an IP address (probably 196.35.72.14)
3) On your machine, in a web browser, type http://196.35.72.14

See if that works, if it does, you have a DNS issues

 

[DFantom]

Sounds likely...FYI DNS is port 53 on TCP AND UDP

 

[Woofda]

I don't think it's a DNS issue. When I ping a site outside of our LANs (from my place), like www.saix.co.za, it is resolved to an IP address, but never gets a responses. Same for web browsing (e.g. www.google.com, MS Internet Explorer reports "connecting to xxx.xxx.xxx.xxx - some IP - at the bottom). I also use the IP address for the Telkom gateway that I can see in the Netgear ADSL modem's configuration.

Yesterday, I set up a laptop at my place to use the ADSL modem/router as the gateway. The DNS is set to the same as the gateway (i.e. the Netgear ADSL modem) Same problem as always. I can ping the ADSL modem, and the IP assigned to it by Telkom too, but can't ping the gatway on the Telkom side.

I then took the laptop over to my friend's place and it worked fine. I changed absolutely nothing except the physical location of the laptop. The IP address was hard-coded (not DHCP), so even that was the same. The only difference I can think of is that I was now not coming in over the Senao wireless bridge. How is the bridge changing the packets so that I can't access anything on the Telkom side of the ADSL modem?

Thanks for the ideas so far.

 

[freeek]

do you have a dns on your lan settings? You must... It won't work without dns settings installed. I have a similar setup. You have 2 have a dns, put saix ones in
196.25.1.1
196.25.1.9

 

[Woofda]

When I do my tests, I'm typing in IP adresses (i.e. 123.456.789.012 type adresses), so I really don't think DNS is involved.

The Netgear ADSL modem lists an IP address for the gateway on the Telkom side of the ADSL link (I'm seeing this on the web interface for adminning the device). I can't ping that address from my place (i.e. when I have to go through thte Senao wireless bridge to get to the ADSL modem), but when I take the laptop over to my friend's place (i.e. I'm on the same LAN as the ADSL modem, no bridge involved), I can ping it fine.

Any ideas?

 

[Woofda]

Note that there's no problem accessing the IP addresses on my friend's LAN from mine (over the Senao wireless bridge).

I can access the admin web page on the Netgear ADSL modem/router from my place. Only IPs on the Telkom side of the ADSL router are not accessible, unless I bring the laptop over to my friend's place, which sorts out the problem.

Very confusing.

 

[Woofda]

I think the Senao bridges have some setting for a gateway IP address.

I have left this unset (0.0.0.0), thinking that it wouldn't be needed (A bridge just plonks traffic from one LAN onto the other one, right?). I'll try setting it to the IP of the ADSL modem/router when I get home and see if that sorts out the problem.

 

[rsachoc]

Good idea, let us know...

Choc

*edit* post a tracert to something like www.is.co.za, and maybe we can do some more troubleshooting

 

[Woofda]

Thanks for all your help - the problem is now solved.

The problem was me not understanding what the Senao bridges do. I thought they just blindly put traffic from the one LAN onto the other one. That's why I didn't think I had to set the gateway on the Senao's. The machines on my LAN all had the gateway set (and the neytmask indicating when traffic should be routed to the gateway), so it didn't seem necessary to set it on the bridges. I was wrong.

I still don't fully understand what the Senao bridges are doing. For example, imagine that one of my machines on my LAN is set up with IP 192.168.1.10, netmask 255.255.255.0 and gateway 192.168.1.1 and I try to access 66.234.345.67 from the machine. The machine knows that the address I'm trying to access is not on the LAN (by using the netmask) so it sends the packets to the gateway. Why the bridge has to have the gateway set too is a mystery to me. I can access other IP's on the other side of the bridge (e.g. 192.168.1.12) without having the gateway set on the bridge.

Anyway, thanks again for all your ideas and help. Let me know if you can explain what the Senao bridges are doing with traffic addressed to IP's outside of the LAN (i.e. why the bridges need the gateway set when the PC's on the LAN already have it set). Thanks,

Woofda