Can't ping webserver...

My friend in another state is trying to setup his webserver at home...

He has a dyndns account setup, his ports are forwarded on his router at home but can't access the website from an outside source. He can however access the website from inside the network.

He can't ping the IP address from outside but we both have been able to SSH and FTP into the server from the outside.

Any suggestions about what might be the problem?

BTW I think he is running slackware on the server.

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Comments

Judd

Megadeth4168 wrote:

He can't ping the IP address from outside but we both have been able to SSH and FTP into the server from the outside.

Make sure his router isn't ignoring ICMP requests, most routers have a feature to allow or deny these request. Check that and see if he can get a reply to his WAN IP address.

Ping the IP and if you get a reply, make sure he has an exception in both the router and software firewall for the port and internal IP he wishes to serve web pages from/to. Ensure his webserver is configured for the same ports as the router and soft firewall and that his NIC is recognized by the webserver with the internal IP address of his network.

By transmitting on ports 21/22 you've ruled out that it's the wrong IP and whether his devices are recognized properly. It sounds like a layer 3 issue with allowing HTTP traffic to the server.

There is always the chance that his ISP is blocking port 80 traffic to residential nodes, this is unfortunately becoming very common as I help people with this all the time and end up finding out that in their acceptable use policy it states that HTTP requests are dropped at the CO.

Good luck and let me know how it goes.

Megadeth4168

The IP we were trying to ping is teh WAN IP... Gives a request time out... Accessing the site from teh outside also give a time out right away. I think what you said about the ISP blocking that may be the case.

I will tell my friend to look over the use policy.

Thanks

Chivalry1

It would be my thought that the ISP has shutdown port 80 local home users. DynDNS is becoming more popular for homeusers these days so ISP's are attempting to limit bandwidth by blocking this port. Try moving the web service to another port like 8080.

I am sure that the ping issue is related to the fact that a software firewall is blocking ICMP packets. Check the local router and then check slackware firewall settings to ensure that it can respond to ICMP packets from the net.

Megadeth4168

I called my friend and he looked into the ISP issue. Indeed you are correct, they have shut down port 80.

I see you mentioned changing the port... I don't want to suggest this to my friend if it will get him in trouble... What do you think?

Thanks

Judd

Megadeth4168 wrote:

I called my friend and he looked into the ISP issue. Indeed you are correct, they have shut down port 80.

I see you mentioned changing the port... I don't want to suggest this to my friend if it will get him in trouble... What do you think?

Thanks

I was pretty sure that would be the case but wanted you to look at the other things to rule them out.

You can change the port as suggested, which is very popular, and see if that works. There is the ethical dilemma involved with that though that only he can decide. If the specifics of his EULA state that NO http traffic requests can enter his residential line then that answer would be no. If it states that a commercial webserver cannot be run from his residetial line then he CAN have a personal webpage ran from his line.

Then he should legally be able to redirect those requests to a reserved http port such as 8088 or 8080. He'll of course have to append the port to his DynDNS name as well as his server address. IE: 10.20.30.40:8088

Megadeth4168

I will pass that along.
Thank you