[plug] David's ADSL Problem

[Harry McNally]

Daniel Pearson wrote:
> Just an update on it for you Harry - I just popped around to his place 
> to have a look.
> 
> The modem is all setup and working, going through the modem's webpage it 
> appears to be in router mode, and doing a ping from the modem through 
> it's interface it can successfully ping 203.0.178.191.
> 
> Now, on the PC /sbin/ifconfig brings up 192.168.1.100 (through DHCP) as 
> the IP address, with the broadcast as what it should be also.
> 
> /etc/resolv.conf
> search
> nameserver 192.168.1.1
> 
> I could ping the modem (192.168.1.1), however was unable to ping 
> 203.0.178.191.
> 
> Typing in "route" only showed the loopback.
> 
> Firewall in the way?
> 
> Wasn't too sure on how exactly the distro is setup (even though it's 
> based on Debian) and didn't want to play around with it in case I get a 
> slap on the knuckles from you! :-)

LOL. No you're fine Daniel ;-)

Thanks for going and having a look. You have now met David. The problem 
is that David keeps asking the list and we are all trapped in Groundhog Day.

Here's my Groundhog Day that is similar to yours but with a few more 
steps and without a house call.

Feeling bad that David didn't have ADSL for Christmas, on Christmas Eve, 
when I should have been taking Jacqueline out to dinner, I rang David 
and proceeded incrementally into what became a 4 hour discussion, 
including with the support person at Conceptual.

So I could start from something I knew would work. I had David use a 
test dialup account that Westnet provides as part of their sponsorahip 
of CA. David has two landlines so testing could be done while he 
remained on the phone. We also rearranged his modem wiring so he had 
both the dial-up and ADSL modem in circuit. I got David to dial-up and 
start sshd. We don't have a firewall on his version. We do on the latest 
one. I could then ssh in and have a look at things. I setup eth0 as 
static 192.168.1.2 so we could talk to the ADSL modem. I grabbed the PDF 
manual from Netcomm and found that the screen shots are entirely 
different to the one that he has. Grrr. I had him reset the modem to 
factory defaults (reset button on the back) and re-enter his user name 
and password. Setting eth0 back to dhcp and down/up and it correctly 
obtained the first factory default IP; 192.168.1.100. All good.

I then brought eth0 down again and had David disconnect from the 
internet (dial-up), change our Internet Settings utility to Broadband 
(ADSL) and let the ADSL come up normally. David was able to ifconfig and 
see the IP as 192.168.1.100 and describe /etc/resolv.conf to me (same as 
Daniel observed above). All seemed well.

It was possible to use host to obtain westnet and conceptual IP and also 
possible to ping them by name. Progress. But according to David firefox 
and thunderbird would not obtain web pages or email respectively :-(

I used wget to get a CA web page. 
http://www.computerangels.org.au/start.html
David was able to assist me to see that a file called start.html was in 
his home dir but I never got him to check it's size so I now wonder if 
wget just created a zero length file. Can anyone comment on wget's 
behaviour if it can't fetch pages for "undefined reason" ?

In exasperation I got David to restore his own dial-up connection and 
email and browsing worked fine. I then explained that I would need to 
think it through and also have Christmas off and contact him when I had 
some more ideas.

Cameron later that evening suggested using w3c to check if it really was 
a firefox issue but we'd restored the dial-up at that stage and I'd left 
David to run like that. We also discounted MTU values too but perhaps 
that is something to check.

I never got to getting the ADSL IP to see if I could ssh in over that to 
confirm the things that David was reporting to me. I assumed the modem 
had some firewall in place and, after 4 hours I had run out of 
enthusiasm :-/

> So that's pretty much where its up to, take it as you will as to where 
> to go to from here.

Since we have not had any issue with any of the other ADSL setups, my 
first step is to drop another hard disk with our standard installation 
onto his system. David assures me he has not made any changes which 
means the first step is to go back to our standard base (if you see my 
approach). David has installed software before using Aptitude and 
various plug-ins for Firefox with some success.

Failing that, I recommend to any of our participants going onto ADSL for 
the first time that they purchase the modem from the ISP. David arranged 
the ADSL under his own steam including wandering into a shop and buying 
an ADSL modem. Conceptual supply DLink. I think David would have 
improved his chances somewhat if he had asked us first and obtained the 
modem from Conceptual but the next step is to try and figure out if 
there is some issue with the ADSL modem.

The fact that Daniel was observing less functionality than I'd achieved 
suggests that David may have done some more work on the problem himself. 
I'd really want to start again with the modem from factory defaults.

I really want a break from Computer Angels since it consumes a large 
part of my life atm (when it needs to consume less). Jonathon (PC-PHIX) 
suggested he would be able to drop out on the 9th January which is when 
we are open at CA again too. I'm trying to stay away from CA stuff until 
then :-)

If other people have some ideas (particularly if you know the Netcomm
ADSL modem well) by all means keep going but I'm going to set this aside 
and have a rest from David's issues for the moment :-)

It's standard Debian sarge, no firewall (on David's machine) but no 
services running either.

One thing to note is that it appears to be important to disconnect the 
dial-up net connection before using the Internet Settings utility so the 
routes etc stay sane. When I first started remotely checking the 
problem, I actually got David to select "No Connection" and then reboot 
the machine to make sure I had forced everything back to a sensible 
state. If you want to flip between dial-up and ADSL, you should use 
Internet Disconnect (off our custom XFCE panel) first.

All the best
Harry