Ping works, trace route works, but nothing else.

G

Guest

Guest
Archived from groups: alt.comp.networking.connectivity (More info?)

Here is one for the TCP/IP gurus of the world.
I am unable to bring up any page from the www.t-mobile.com web site.

Here is what I checked:

1. People on other networks are able to bring the web site up fine, so
t-mobiles web server is up and running.

2. I tried using both IE and Firefox web browswers to bring up the
home page but neither work.

3. I did an nslookup on www.t-mobile.com and DNS is working fine. I
got the correct ip address of 65.161.188.152.

4. I issued a ping to www.t-mobile.com, and all worked perfectly. 4
packets sent, 4 received.

5. I issued a trace route to www.t-mobile.com, and again, all worked
fine.

6. I tried to telnet to port 80 on the web server at www.t-mobile.com
to manually issue a GET for the home page, but the telnet connection
never completed.

7. I called my local ISP to ask them what they thought was the matter,
and they were left scratching their heads. There was some speculation
that perhaps there is a missing route statement for the route back.
Which begs the question, are ICMP messages unaffected by a missing
route back statement that TCP is affected by?


If anyone has a solution to the problem that I'm experiencing here, I'd
be grateful to hear about it.

- TN
 
G

Guest

Guest
Archived from groups: alt.comp.networking.connectivity (More info?)

> are ICMP messages unaffected by a missing route back statement that
TCP is
> affected by?

No, AFAIK the routing table must be correct for ICMP to work. In other
words, if you can ping and traceroute, I don't think the routing table
is wrong.

But do you have some kind of firewall (software/hardware) which might
block HTTP (port 80) requests? However this would be unlikely, if you
can visit other sites.

Finally, T-Mobile might block HTTP requests from you or your ISP (not
knowing why exactly this would be, but a possibility nevertheless).

BTW, how do your browsers react? do u get a time out, error message or
just blank page?

HTH
Andreas
 
G

Guest

Guest
Archived from groups: alt.comp.networking.connectivity (More info?)

Thank you for the reply Andreas.

With Firefox, I get no response when trying to connect to
www.t-mobile.com. No error message. I just get a blank page.

IE reports "The page cannot be displayed"

Now I do have a firewall/router, the denies inbound connections, but
permits all outbound connections.

I also have the Windows Firewall running on the machine that I use to
surf the internet, but I have currently have that firewall completely
diabled.

Just for the heck of it, I'm going by pass my firewall/router and put
my PC right on the internet, but my hunch is that this will not fix my
problem, given I have no outbound restrictions on this firewall. Stay
tuned.

- TN
 
G

Guest

Guest
Archived from groups: alt.comp.networking.connectivity (More info?)

Thank you for the reply "Giganews". Your post helps.

I am certain I have come accross this problem in the past when I used
to handle various networking duties for a formor employer....but I'm
not a CCNP, and WANs was never my sole area of focus, so I'm uncertain
about some of the nitty gritty details of TCP/IP, but knowing that
another has had the same problem with the same ICMP/TCP issues, bosters
my confidence that the problem has to do with the route back.

I have contacted T-Mobile, but they have been useless. I have not even
been able to get to a person yet who understands networking issues.
I've only been able to contact high level help desk folks who, while
nice enough, don't know enough.
Thank you. I'm going to do more research on the problem.
 
G

Guest

Guest
Archived from groups: alt.comp.networking.connectivity (More info?)

It could still be a routing issue. I had something very similar to this
happen at my company. However, I had the fortune of being able to access the
webserver and trace back to see that the packets initiated from the
webserver were taking a completely different route back. My situation was
identical to yours...ICMP would pass, DNS worked, telnets on :80 would not
work.

Here's what ended up happening:

I had an office in AZ that was unable to access my companies website. I was
able to remote into their server and see that the pings were making it over
the their ISP's network, through the handoff, into our ISP's net, and
finally to my webserver. If I did a trace back to their server from our
corporate webserver, the route would vary a bit in that it was hitting a
different router on the remote site ISP's network. I could see that the
packets were being dropped by a gateway router (.68) Even stranger was if I
initiated the trace from another webserver in the same subnet at out Corp
office, it would make it back to the remote site, but using a different
router on the ISP net as the 2nd to last hop.(.70) It ended up being an
issue with the ISP's routing table on that one router. Anytime traffic
originated from the inaccessible webserver, it would always be dropped by
that gateway (.68) router on the ISP network.

They were able to take a look at their routing tables and get the issue
corrected. It will be harder for you to prove this to the ISP, b/c you wont
be able to send them traces from the webserver, but if you call T-Mobile and
explain your sitch, you me be able to get someone willing to help...all they
would need to do is run one trace for you.

Hope this helps...


<teck_nickle@yahoo.com> wrote in message
news:1106319856.279607.122590@z14g2000cwz.googlegroups.com...
> Thank you for the reply Andreas.
>
> With Firefox, I get no response when trying to connect to
> www.t-mobile.com. No error message. I just get a blank page.
>
> IE reports "The page cannot be displayed"
>
> Now I do have a firewall/router, the denies inbound connections, but
> permits all outbound connections.
>
> I also have the Windows Firewall running on the machine that I use to
> surf the internet, but I have currently have that firewall completely
> diabled.
>
> Just for the heck of it, I'm going by pass my firewall/router and put
> my PC right on the internet, but my hunch is that this will not fix my
> problem, given I have no outbound restrictions on this firewall. Stay
> tuned.
>
> - TN
>