I have a strange issue. I just setup a linux web server with Ubuntu and it works great from all my internal pcs going to the internal address ( 192.168.1.13 ) however when I try to go to any of them from the outside address it says it cannot find the server. Now I have gone in to my linksys router and setup port 80 to be forwarded to the internal .13 address. the online linksys support person said they could go there and even told me what was in there so they say it however every pc i have tried from inside can not view it from the outside address. I tried 3 windows pcs and a sharp zaurus pda. all same problem cant see it from outside but can from internal address. anyone have any ideas whats wrong and how i can fix this? Thanks!

Why do you need to hit it from the external address when you are on the inside? That usually works with home routers (Linksys,etc) but doesn't work with real firewalls. Do you really want the traffic to go through a cheap router and back in when you could just hit it directly? If it's a DNS issue, I would suggest running an internal DNS server with a bogus record for the host pointing to the inside ip.

That's normal. When on the inside, use the inside address, when on the outside, use the outside address. I'm pretty sure the problem has something to do with the NAT. If you got a router that was capable of putting the web server in a DMZ, it would probably work just fine.

Yeah, what he said. Trying to access the external IP address from within a NATted network is a relatively complex problem that is relatively difficult to solve, and it's not really a problem that causes much grief, other than having to have multiple DNS zones, which you probably need anyway, in order to not show off your internal addresses to the Internet.

In other words, don't do that. Typical of the Linksys tech support guy to not mention such a basic thing (that they're bound to encounter every day) to you.

Well the reason I was trying it was cause I set up a Dynamic DNS software package and was trying to go to my domain to verify it worked but it kept coming back as server not found so then I decieded to try just the ip address to see if it worked that way. I just would like to verify how it appears to the outside world. unfortunitly my router is part of my cable modem (Linksys WCG200) so I cant set up a connection outside of the firewall. I did see a DMZ option in there I guess I could try that. Thanks for the replies!

You could IM one of us with your domain name and we could check it for you.

You don't need a DMZ or extra DNS zones or anything like that. You merely need a capable router.

Our Cyberguard SG575 (running Linux) does it just fine
Our previous firewall, a ClarkConnect Linux machine (Redhat based) worked fine.
Our very old ipchains based RH6.2 system didn't work properly and worked exactly as you describe.

I decieded since it works I just cant see it from the inside im going to leave it alone and just stick with going to the internal address.. Thanks for telling me thats how it works.

Yeah, but those all implement a general-purpose firewall, whereas the consumer routers are explicitly single-purpose things, and they have no desire to make that sort of stuff work. It's not that it's an impossible task by any means, but it is significantly more complicated than not doing it.

Well, I know going to the external address worked on my old negear home router. (though I can't remember if it was the sardine can, or it's predecessor, the Real Metal Case router) However, it worked extreemly slowly and wasn't usable for much. Using the internal address will prevent the traffic from having to traverse the router, so it's bound to be faster.

Matthew

the only problem i had was as i create pages using my domain name when trying to view the pages or my user account activation link in an email it doesnt work. Its workable just a pain. Thanks for your help with the issue.

You can probably fix this by putting an entry in your hosts file with the internal address. Should make the links work easily enough.

Matthew

OMG i feel so stupid now, after all this trying to figure out whats wrong all i had to do was that little entry and it works perfectly.