Getting around port 80 block [SOLVED]

[Greg Rundlett]

Since my machine had not rebooted, I did not anticipate that the
dynamically (DHCP) assigned IP address might change.  In a panic, I
figured Comcast was blocking my port 80 traffic.

Just as I was about to send this email, I did a couple more checks and
that's when I realized that the local host changed from 192.168.1.126
to 192.168.1.128.  All I had to do to fix the problem was change the
existing port forwarding rules in my router configuration. /me slaps
forehead.

-- read on though in case it's amusing. :-)  For the record, I believe
I was doing the correct drill if this had been a real emergency.

All of a sudden, my local Apache server is unreachable.  It works just
fine from http://localhost, but when trying to reach it from the WAN
side, requests time out.  I suspect that Comcast is blocking port 80,
so I tried to listen on another port, but that isn't working either.

What I did was
* edit Apache's config to listen on 12354
* restart Apache
* edit the "Gaming" rules on my router to forward requests on port
12354 to the IP of my Apache host
* verified that Apache is responding at http://localhost:12354
* tried to access http://24.128.37.249:12354 (request times out)

So, I ran nmap (using the zenmap GUI).  The output is included below.

If I can establish a connection, then I assume that I'd be able to use
my zonedit.com web forwarding service to redirect www.rundlett.com to
local.rundlett.com:12354 giving users the same result that existed
previously.  But first I have to figure out why I can't seem to
establish a connection on a higher unprivileged port.

There is no firewall running on the host.

Oh wait, let me try to access it from another host on the network just
to be sure... It's not responding.. let me check that I have the right
local network address.  OOPs, my bad.


Scanning 24.128.37.249 [1715 ports]
Discovered open port 10000/tcp on 24.128.37.249
Discovered open port 4000/tcp on 24.128.37.249
Completed SYN Stealth Scan at 16:14, 3.10s elapsed (1715 total ports)
Host 24.128.37.249 appears to be up ... good.
Interesting ports on 24.128.37.249:
Not shown: 1711 closed ports
PORT      STATE    SERVICE
22/tcp    filtered ssh
80/tcp    filtered http
4000/tcp  open     remoteanything
10000/tcp open     snet-sensor-mgmt

Read data files from: /usr/share/nmap
Nmap done: 1 IP address (1 host up) scanned in 3.181 seconds
           Raw packets sent: 1727 (75.968KB) | Rcvd: 1714 (78.844KB)



-- 
Greg Rundlett
Web Developer - Initiative in Innovative Computing
http://iic.harvard.edu
m. 978-764-4424
o. 978-225-8302
skype/aim/irc/twitter freephile
http://profiles.aim.com/freephile