[NTLUG:Discuss] how do i know if port 80 was blocked?

Alton R. Pouncey, II alton at trainers-r-us.com
Fri Jan 3 15:29:16 CST 2003


On Fri, 2003-01-03 at 14:36, m m wrote:
> Thanks you all for the reply.
> I am sorry that I should ask this question as:
> 
> How do I know if at&t block incomming http request to/for the ip 12.237.x.x?
> 
> the problem is the I have setup a web server, and just don't work (it worked 
> before I change cable modem, of course I registered the new MAC address). I 
> have heard that the at&t block the port 80 on some area. I wonder my web 
> site don't work because they block port 80 on my ip.
> 
> thanks.
> 
> 

Start you web server then go to http://uptime.netcraft.com/up/graph/ and
enter your ip address in the box on the left side of the page under the
question "What's that site running ?"  If it can't get to your website,
no information will come up and you could possibly be blocked.

> 
> 
> 
> >From: MadHat <madhat at unspecific.com>
> >Reply-To: discuss at ntlug.org
> >To: NTLUG-Discuss <discuss at ntlug.org>
> >Subject: Re: [NTLUG:Discuss] how do i know if port 80 was blocked?
> >Date: 03 Jan 2003 14:20:44 -0600
> >
> >On Fri, 2003-01-03 at 14:05, Philip Stetz wrote:
> > > --- m m <llliiilll at hotmail.com> wrote:
> > > >
> > > > Hi all:
> > > > Is there any to find out if the port 80 was blocked?
> > > > IP 12.237.x.x from at&t
> > > >
> > > > thanks
> > > >
> > >
> > > you can use nmap to do a port scan on that ip.  some
> > > sys admins may frown upon that though :)
> >
> >Depending on how the router/firewall is configured, it may or may not
> >tell.  If it just drops the packets, you can't tell if it being blocked,
> >or his machine just doesn't have anything on port 80.
> >
> >If the router sends an ICMP prohibited message, nmap will show filtered,
> >but that is not always accurate, as some timeouts will show filtered as
> >well.
> >
> >If the router sends a reset it will just show closed, even though it may
> >be blocked.
> >
> >To be 100% sure, start up a sniffer on the 12.237.x.x machine and then
> >telnet to port 80 to it from a machine on a different network and look
> >for the traffic in the sniffer.  If it shows up, it isn't blocked.  Of
> >course you can still use nmap, but that is overkill.  You can also use a
> >plethora of other tools like netcat or any other port scanner, but
> >telnet is easy and will do the trick.
> >
> >
> >--
> >MadHat at Unspecific.com
> >`But I don't want to go among mad people,' Alice remarked.
> >`Oh, you can't help that,' said the Cat: `we're all mad here...'
> >    -- Lewis Carroll - _Alice's_Adventures_in_Wonderland_
> >
> >_______________________________________________
> >https://ntlug.org/mailman/listinfo/dis
> 
> _________________________________________________________________
> Protect your PC - get McAfee.com VirusScan Online 
> http://clinic.mcafee.com/clinic/ibuy/campaign.asp?cid=3963
> 
> 
> _______________________________________________
> https://ntlug.org/mailman/listinfo/discuss
-- 
Alton R. Pouncey, II
SCSA, SCNA, CCNA, CIW Professional
http://www.trainers-r-us.com
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 232 bytes
Desc: This is a digitally signed message part
Url : http://ntlug.org/pipermail/discuss/attachments/20030103/7f6012b5/attachment.bin


More information about the Discuss mailing list