Troubleshooting and Documentation

One of the most difficult, most stressful, and most common tasks for a network administrator is troubleshooting problems. No matter how well your network is designed and runs, sooner or later, you will have to troubleshoot some sort of network or server issue. If you stay calm and follow a step-by-step, logical plan to track the problem, you should be able to get the issue resolved as quickly as possible. Here is an outline, based on the CompTIA Network+ troubleshooting methodology, to follow to help resolve your issues:

1.	Identify and document the symptoms.
2.	Determine the severity of the problem and which users are affected. For example, is the entire network down, are just the users on a particular switch down, or is everyone who uses a specific database down?
3.	Determine what has changed on the network (hardware, software, driver or operating system patches, and so on). Jerry Pournelle's classic question, "What changed since the last time [the network] worked?" is a useful way to summarize this step.
4.	Determine the most likely cause of the problem. Make sure users understand how to use the network (user errors often cause problems), and check physical and logical connections on the network. To determine whether you have discovered the actual cause of the problem, re-create it and apply your suggested solution on a test network (if possible). If the re-creation and solution appear to work, proceed to step 5.
5.	Implement the solution developed in step 4.
6.	Test the solution on working systems.
7.	Recognize the side effects of the solution and prepare to deal with them. Examples include client software updates and IP address type changes.
8.	Document the solution and make sure support and management staff understand the problem and the solution. Make the information available through an online database or a FAQ list, or via some other manner that is easily accessible.

Tip

If you are managing a network, you should consider using a system for tracking tech support calls and solutions. This type of software is sometimes referred to as a trouble ticket system. Some examples include the following:

• Open Ticket Request System (OTRS; http://otrs.org)

• AnswerTrack trouble ticket system (www.answertrack.com/marketing/trouble_ticket_system.html)

• Trouble Ticket Express (www.troubleticketexpress.com)

In finding solutions to almost any problem with your server or network, documentation is a precious resource. In fact, documentation is one of the most important tools when you are trying to troubleshoot or upgrade a network. A network administrator needs to have everything documented for ease of use and to be as efficient as possible in everyday administration, but even more so when there are problems. You can know everything there is to know about your network when things are calm, but when something goes wrong and all the pressure is on your shoulders, you tend to forget some of the little details, and your thinking can sometimes be a little less reliable than usual. For this reason, it is nice to have network diagrams and documentation to help keep a clear picture of what is going on.

If you decide to upgrade items on your network or add features and servers to your network, your network documentation can help you avoid having problems. For example, you could run into little problems such as an IP conflict that could take a little bit of time to track down, but if you have your documentation handy, you could quickly look and see what IP addresses are available and make sure that you never run into that issue to begin with. You could use your documentation to make sure that you continue using the same naming context for your devices. When running a network, attention to details and all the little things really make your network run smoothly in the long run.

Tip

Network documentation software can help you easily diagram and capture network information. Some leading titles include the following:

• Neon Software's LANsurveyor (www.neon.com)

• SmartDraw Technical Edition (www.smartdraw.com)

• Microsoft Visio (www.microsoft.com); note that many vendors make add-ons for use with Visio, including Altima NetZoom (www.altimatech.com) and Neon Software LANsurveyor for Visio (www.neon.com)

If you have a network that is not large enough to require a network administrator, your documentation could be even more important. Good network documentation can help you solve problems without needing to call in network consultants. However, even if a network problem becomes so difficult that you need to bring in a network consultant, you will save time and money by providing the consultant with accurate and up-to-date network documentation. Otherwise, the consultant will need to determine how your network is configured. At typical rates of $150 to $250 per hour, the time needed to determine configuration information can add up quickly.