Server works with internal IP but not external

Help! (Home for newbies)
1

I am trying to setup my first server, but having some trouble. I am a newbie so forgive me if its something stupid I have done wrong.

I setup Virtualmin and it’s “Checking Configuration” passes. My server’s internal IP is 192.168.199.91. When I visit that IP on my local network, it pulls up a website, and if I add the port it pulls up Virtualmin.

If I try to visit my external IP from another network, it just times out. If I add the Virtualmin port, I get nothing. I’m suspecting it is a networking issue.

My external IP address is: 173.12.247.xxx.
In my router I am forwarding “All Traffic” from any source to my server’s local ip of 192.168.199.91.

On my server, here is my routing info:
[root@ns1]# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.199.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
169.254.0.0 0.0.0.0 255.255.0.0 U 1002 0 0 eth0
0.0.0.0 192.168.199.5 0.0.0.0 UG 0 0 0 eth0

The 192.168.199.5 is the internal IP of my router, so that is correct. I have no idea what that second line is starting with 169.254.

Does anyone see anything or have any ideas as to why I can’t hit my server from my external IP?

Thanks!

2

Howdy,

Well, the first thing we can test is just to make sure that your server is seeing the Internet.

To do that, if you log into the command line, you can run a command like this:

ping google.com

Do you get a ping response back? Or do you receive an error of some sort?

-Eric

3

When I ping google.com, it returns:
ping: unknown host google.com

I tried to ping one of google’s DNS servers 8.8.8.8 and it works fine. So maybe I have some DNS issue?

4

Well I found the problem! My comcast business modem has a firewall turned on. I put my router as the DMZ and now everything works! Thanks for your quick reply!

5

Super, I’m glad you got it working, thanks for sharing what you did to fix it!

-Eric

6

I must still have some networking issues. I have been setting up e-mail accounts and the server receives mail fine, but can’t send. So I try to telnet google’s mailserver and hotmail to test my connection, but it can’t connect. I realize that I have been having problems installing packages from webmin/virtualmin because it can’t resolve the domains.

It seems like the server can’t see the internet, yet it can be found. I am trying to figure out how to further diagnose this issue so I can fix it. I am not sure how to configure my networking other than the default settings. Is there some test I can run or place I can look to see if something is off?

Well, some things work. Like I can ping google.com, so the DNS obviously works. But telnet, and Virtualmin/Webmin’s installing packages doesn’t work unless I download the file manually via wget first.