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I have setup an Ubuntu 10.04(LTS) server at home that is used as a web server. Primarily to give me access to my private cloud where I have 2TB of storage available to me. I am using OwnCloud for this and I installed Webmin to make administering my server easier. I am also running FOG server which is an imaging server that allows PC's on my network to boot via PXE.

I got everything setup yesterday and was even able to login to my server using my domain ( I can view my root index page and access everything just fine when I'm using my home PC, but while I'm at work, I can't reach the default page, or anything else on port 80. My router on port 8080 is accessible, my Webmin interface is too (port 10000). I can even remote into my server over SSH (port 22), but port 80 seems to be dead.

I called Comcast and they told me that the port was not being blocked. I can't figure out why port 80 will not go through while I am at work, but works fine at home. Also, I am using an open access point from work, so as to go around all their network restrictions. I have even tried using the WiFi hot-spot powered by my phone with the same results.

Any help is greatly appreciated.

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closed as off topic by Wesley, HostBits, Sven, Iain Apr 17 '12 at 21:56

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Can you nmap your domain from work and at home and see if port 80 changes from closed to open? – Robert Mason Apr 17 '12 at 21:42
Some routers just will not forward port 80. Others will, but only if you dig out specific settings in odd places. (Make sure you've moved the management web server off port 80. On some routers, you have to do this in two places -- one for local admin and one for remote.) – David Schwartz Apr 17 '12 at 21:49
up vote 1 down vote accepted

Likely your ISP is blocking port 80. It's very common, unless you have a "business" line.

I called Comcast and they told me that the port was not being blocked.

If you ever trust what an ISP tells you, I have a bridge that might interest you.

Nevertheless, if you think that the ISP is telling the truth, you can simply banner grab the HTTP server using telnet and see what the response is. If your router has port 80 open, and is forwarding to your web server, and yet you can't get through - then your ISP is blocking port 80. Take that evidence to them, open a technical ticket and prepare to flirt with the idea of substance abuse to numb the pain.


ISPs are liars.

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"flirt with the idea of substance abuse to numb the pain" -- nice :) – Andre Lackmann Apr 17 '12 at 21:47

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