Troubleshooting Potential Problems

Problems with even a basic network diagram can crop up in numerous places. The first thing to do when you have any kind of traffic routing problems is to check all connections. The simplest solution is sometimes making sure all hardware is plugged in and turned on. Check all the cables and make sure they are plugged in. Hardware can be a problem; if something is wrong with your cable modem, that will scrap your whole network. Your hub might have a bad port that will not route traffic. Ensure that all the hardware is functioning properly.

When you have determined that your hardware is functioning properly, your next step is to check your firewall rules. You can do this in several ways. One option is to turn on logging on all firewall rules and see what is happening to your traffic. You also can remove all the rules and then start adding one rule at a time to make sure that each is working properly. A third option is to allow all traffic through and ensure you are routing traffic and then start locking down each rule and determine where you break the network.

Windows 2000 and Windows XP come with built-in filtering capabilities. The operating system also can be a problem when it comes to filtering rules. If you enable some of the filtering capabilities in the OS and forget about them, your system could experience problems. If you are using other third-party firewalls on your internal systems, these can also cause a problem. You shouldn't run more than one firewall and antivirus scanner on each system. Software will most likely be the source of your problems.