D Link, BT broadband...and pain!!

My BT broadband works fine with by Homehub. But its a homehub so its being replaced. I picked up a D Link modem as a starter (DSL 320B). It comes preloaded with most the settings for BT. Only had to add the username and password. WHich given I've tried a dozen versions, including that given to me by BT, will seem a bit more odd in a moment.

Thw web interface on the modem claims the net is up and running, all diagnostics passed, including authentication regardless of what the username or password happens to be.

But no net connection. Ping from the attached PC gives me "net unreachable". Its not the PC setting as if I ssh into the modem I get the same if I try to ping anything on the net including the gateway its supposed to be connected to. And if I look at the stats there are plenty of packets and data moving on the LAN but zero - utterly zero - on the WAN.

Does anyone have any ideas what might be causing this as I'm going round the twist now.

Thanks in advance.

Bob

Thw web interface on the modem claims the net is up and running, all diagnostics passed, including authentication regardless of what the username or password happens to be.

presuming this is a bt home (not office) connection that is correct, it is authenticated by the 'line' ie the physical 'phone line connection.

I suspect your pc's default gateway is incorrect, ensure you are using dhcp rather than assigning a fixed address to it. (and restart the pc)

I wondered if that was the case - there's just such a faf at BT with what the log in details should be. If only they just came clean about it.

If the PCs gateway is incorrect would I not still be able to ping from the modem (after ssh'ing into it)? At the moment it gets the same result - net unreachable.

Could it possibly be that there isn't an open port allowed by the firewall?

BT residential don't use passwords and the username is generic and pre-loaded in the hardware they supply - [email protected] for example

Check that the thing gets a WAN IP from its GUI

Thanks for the further info.

If the modem itself is allegedly connected but can't ping anything on the net would it not bypass any firewall on the PC or similarly ports?

Have you checked to actually see that the IP address and other information handed to the router by the authentication layer actually make sense for a BT Total connection?

It is possible the authentication is taking you to a walled garden, rather than actual internet.

The gateway seems to be the same, as does the DNS handed to it as well. The only thing that changes is my IP, but then its dynamic IP so it's no surprise I guess. The modem's internal config says its connected and authenticated etc. It is officially driving me mental now!! BT no help, D-Link very little help.

Potentially a stupid question but does the modem need "trained"? I remember the original hub needing to be left for a period of time to work, and in certain command line reports on the new modem it mentions training but not really anything abuot it.

Gateway inside the modem, i.e. what BT is handing out

Or what the modem is handing to the PC?

Training in terms of routers like yours is referring to the ADSL handshaking that occurs when you switch the ADSL modem, and it is attempting to sync with the hardware at the telephone exchange.

You are confusing the DLM training period with the standard sync process

Gateway inside the modem yup - according to its GUI and if I SSH into it as well. I figured if I could get the modem to ping smthg on the net that would at least narrow the problem down.

If you take the IP address given to the WAN interface and do a reverse DNS lookup (using another connection) what does it reveal.

If this is old fashioned IPStream it should say BT Central Plus.

Your inability to ping makes me think that while authentication is working, it is really failing and dropping you at a walled garden. The lack of detail such as IP address, gateway info makes it very much guesswork for people trying to help you.

At end of the day what do you want to achieve? Is this DLink proving worth the effort?

Thanks again. I'll give that a go and see what comes up with it and get back to you.

How much detail would you like re IP address etc? Wasnt sure how much was safe to publicly give.

Probably not worth the effort - but its one of those started so I'll finish type of things really now. I'm a stubborn swine!!

ping the WAN side of your router with http://tools.pingdom.com/ping/
your router may have disabled WAN side ping.

if it's a dynamic IP address who cares if you publish it, we could find it by scanning BT's allocated blocks

I forget, can you actually access th einternet ?

does nslookup www.bbc.co.uk give a sane answer ?

Hopefully I'll manage to answer all the questions here.

Before unpluggin the Hub I checked the reverse DNS and it came back with BTCentralPlus. This was on an IP addy starting 86.156. The new modem comes up with 86.151 but also on BTCentralPlus.

The default gateway for each is the same (217.47.207.58) and the DNS are the same as well. (primary being 217.32.171.21).

Subnet is 255.255.255.255, I can't check that on the Hub though so not sure if its the same.

Tried to ping my Hub from the site given but all the packets were lost but traceroute provided a more successful run. I tried the same on the new modem and the result was almost exactly the same. One tiny difference in an IP half way down the list but otherwise intact.

And allegedly I am connected to the net but to ping anything outside my four walls is futile - even the default gateway or DNS.

Thanks for all your time so far guys.

In reply to a post by Anonymous:

And allegedly I am connected to the net but to ping anything outside my four walls is futile

Due to the netmask being 255.255.255.255. Try reconnecting the Hub and seeing what the netmask should be.

In reply to a post by BatBoy:

In reply to a post by Anonymous:

And allegedly I am connected to the net but to ping anything outside my four walls is futile

Due to the netmask being 255.255.255.255. Try reconnecting the Hub and seeing what the netmask should be.

Unfortunately I can't see any way to check the netmask on the Hub itself and it wont take SSH / telnet to work it out.

Subnet mask of 255.255.255.255 is not uncommon for a single IP allocation - think about it.

Everything is pointing towards the IP being fine, and something simple like NAT is disabled or a firewall is running on the DLink.

Has this modem being known to work for sure on any broadband connection?

It means only packets addressed to 217.47.207.58 will be sent.

The modem is out of the box so it may be faulty. Also I wish I could say I had thought about the 255 etc issue and worked it out but I'm a bit thick about these things (learning fast mind you!!)

Checking ifconfig I have ppp_0_0_38_1 with the IP address handed down from BT and the default gateway listed as the P-t-P. There is eth0 which doesnt appear to be active and then br0 which is the LAN port based on the IP addy.

A quick look through route on the modem show online 1 line being 192.168.1.0 with it saying:-
Destination 192.168.1.0 Gateway * Genmask 255.255.255.0. Am I missing something here? WOuld there be some form of route for the external side or gateway or something?

so the WAN side is working and traceable from outside.

Did you do the nslookup from your client PC ?

does the hub work normally ?

It would seem so. But on the other hand now I've disconnected it - its been out for a few minutes - and traced it again from another PC and its still showing the same results. So I can't actually be sure that the trace is back to my own connection.

I tried nslookup on the connected machine adn got rubbish. Unfortunately the modem itself doesnt come with nslookup on it. But if I ping say 8.8.8.8 network is unreachable.