How to Troubleshoot Enterprise Networks

Troubleshooting an enterprise network uses a variety of approaches.

Every enterprise network has two sources of communication: the host, and the network. Consequently, if problems arise on the network, then the troubleshooting can begin there. But that is not the only way, because the source of the problem may be at the host level. Consequently, the best way to troubleshoot a network operation is with a systematic approach. This takes into account the source of the problem--how to separate and identify the problem for a better understanding of the causes, where the problem may be located, and how to identify nuances that speak to a possible solution.

Instructions

1. Go to the domain controller on the network to start the analysis with the top-down approach. Identify the problem and assume that it originates at the network level. Then look at the routers, the switches, the cables and the domain controller. Find the IP address, the subnet mask, the gateway and the address of the DNS server of the domain controller, and the domain name. This will establish your baseline of information. The problem could be host (local) or network (general). It could be hardware or software. The next few steps will help you identify the range of the problem.

2. Go to the host machine that is having a problem. Go to the Control Panel and select the "Network and Internet" link. Look at the local area connection's properties. Match the IP address gateway, the subnet mask and DNS server IP address. Because you are looking at hosts, this approach is bottom-up.

3. Go to the host's network card, and test the cable connection. Ping the network devices on the same network to test the connectivity. This is the divide-and-conquer approach because it looks at common network components and you can determine if the issue is hardware-related versus a software-related problem.

4. Go to the central network devices, which are the routers and switches. These are the locations where the network converges. This lets you follow the path of the problem around the network. The routers and switches have their own configurations; they control how devices see the other hosts on the network, and even how to access other networks or the Internet.

5. Go to another host device and compare its operation with the networking problem. If you can replicate the problem, then it is network-related; otherwise, it could be host-related.

References

• Informit: Troubleshooting Processes for Complex Enterprise Networks
• Support.3Com: Network Troubleshooting Overview