fwbuilder config not allowing http access using URL, only local IP

syrex · 05-19-2011, 02:45 PM

OK, I believe this is due to a firewall rule.

I have a dual-nic firewall box, using fwbuilder. On my local net, I have a vm running a webserver open to the world via a dyndns URL name.

When behind my firewall, I can only reach that httpd server via the local IP address, but the world can find it by URL name.

Shouldn't I be able to reach it locally by URL name? What would that rule look like?

Thx

smoker · 05-21-2011, 08:14 AM

It's not a firewall issue, it's a DNS issue. Edit /etc/hosts on each machine inside the firewall and add the domain name with its local ip address there.

This assumes you're using linux on the client machines. Under windows XP Win7 the hosts file is under the \windows\system32\drivers\etc directory.

syrex · 06-01-2011, 10:22 AM

I don't see how this can be a DNS resolution issue. Doing a nslookup of my dyndns name resolves to my external IP address.

I think this is perhaps a routing issue, in that the traffic is getting the IP address, and redirecting to the firewall box, but never actually leaving my internal network. For example, I drop ping requests from outside, but I can ping my external IP address by DNS name internally, meaning the firewall is handling the traffic internally.

smoker · 06-01-2011, 04:26 PM

Of course nslookup resolves - that is where the domain resolves to. nslookup does not check the link to your local address - it just checks the registered entries for that domain. Which in your case is your external address. Unless you run a local dns server, you will not resolve your domain locally without entries in the host file.

You can't point a domain at two ip addresses - so how can you expect it to work with an internal and an external address ?