Re: Weird problem, only one port, 80, is blocked.

On Tue, 30 Sep 2008, in the Usenet newsgroup comp.os.linux.networking, in
article <qak2e45okj7smk4nmrsn6jkri5jhpabpl3@xxxxxxx>, Grant wrote:

ibuprofin@xxxxxxxxxxxxxxxxxxxxxx (Moe Trin) wrote:

Obviously dodoau7.lnk.telstra.net or dodomel-lns002-ge3-4-2.core.dodo.com.au
is dropping port 80 inbound. Does your contract with Dodo Oz Pty say
that you are to have such access? If so, raise hell with them.

Hey thanks for that, things looking gloomy yesterday as they trying to
blame my linux + bridged modem setup. Yes I'm allowed to run servers,
been with ISP for four years and had web + ftp server up for most of ]
that time.

OK - I only looked at those two ports, but the results are quite
obvious. Either dodomel-lns002-ge3-4-2.core.dodo.com.au (most likely)
or dodoau7.lnk.telstra.net (possible) is silently discarding packets to
port 80. There were no ICMP errors returned.

What did you use to trace port 80? tcptraceroute?

Yup - that's what it's designed for. You can also use hping2, hping3,
or nmap to do the same thing. Some ISPs don't like you using those
type of tools though.

Dodo tech seem to have no tools, they're a windoze based company, I'm
only there for the cheap ADSL plan ;)

Melbourne? There are alternatives.

Your trace shows what I've been trying to tell them since Friday, it
isn't my end playing up, thanks again for this evidence :)

Glad to help.

Old guy
.

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