Linux - NetworkingThis forum is for any issue related to networks or networking.
Routing, network cards, OSI, etc. Anything is fair game.
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I'm configuring a simple web server behind a firewall. The web server box is running Trustix Secure Linux and has a single ethernet interface, eth0.
I've assigned eth0 an address of 192.168.3.3. I have a laptop (xp), and give it an ip on the same network, 192.168.3.5.
I hook an ethernet cable from my laptop to the web server and ping it. No problem. I ping the laptop from the web server. Also not a problem. So far, so good.
Next, I unplug the laptop and hook an ethernet cable from the web server to my firewall machine on its DMZ interface (192.168.3.4). I try to ping 192.168.3.4 from the web server and I get nothing. The lights on the back of each of the cards are not lit. What does that mean?
That led me to believe that something might be wrong with the DMZ interface. So, I hook my laptop directly up to the DMZ interface. Interestingly enough, the laptop has no problem pinging the DMZ interface. the lights on the cards are on. What gives?
This is just a guess, but are you using the same cable between the web server & laptop that you are between the DMZ of your firewall/whatever? if you are you need to get a normal (non-crossover) ethernet cable.
The router will have the 'crossover' built into its ports so using a crossover cable would stop it working.
In response to skunkburner's post, I am using the same cable to connect the laptop with web server in test 1, the web server and dmz interface in test 2, and the laptop and dmz interface in test 3.
However, I think that something might have been unclear in the original post. The firewall machine with the DMZ interface is just a linux box running ipcop. It has three network cards (one internet, one lan, one dmz). It isn't a special purpose firewall appliance or router.
What about the mode of the web server and dmz interface. Are they both full/half duplex, and are the speeds korrekt 10/100?
If two devices are set to aotu sense there are problem I have heard.
One has to decide and the other will adapt.
Use the mii-tool to see if you can determine the settings.
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