In today's IT environment, network documentation is an absolutely critical element of what an IT professional does. With the growing trend of IT professionals switching companies every two to three years on average it's become increasing important to accurately and properly document your network environment. The downside of network documentation is doing network documentation. It is quite literally one of the most mundane and quite frankly boring aspects of most IT positions.
There are dozens upon dozens of ways to accurately document your network. In truth, there is no "proper" method for documenting your network. As long as you feel that your network environment is "on paper" and accurately reflected, whatever means accomplishes that is proper network documentation. Visio diagrams, Word documents, Excel spreadsheets, databases, and more are all valid means of either documenting your network or having your network documented for you. Which method you use is based upon your personal preferences as well as the requirements by the company that you are working for.
Using Microsoft Visio to diagram your network is a very efficient means of gaining an accurate visual representation of your network. Visio features an interesting feature, which allows you to auto document your network in Visio. Visio itself performs network discovery by basically pinging available devices on your network. Once the devices return a successful ping Visio attempts to perform an SNMP query on that device to try to learn more information about it. From there it adds it to your Visio diagram. While in practice this functionality may sound very useful, in actual implementation the many times that I've run it the end diagram requires a very large degree of modification. Visio itself seems to have problems accurately determining which equipment falls under which hub or switch or router and sometimes will even lump them all into one large sum or pool of devices.
Using Visio there are many different ways to document your network which vary depending upon the method of diagramming you wish to do. You can diagram from a building level, a network level, a user level or many other variations. One method that I personally have preferred to utilize is a combination of both building level and network level. When you diagram from a building you are merely diagramming the physical layout of where network devices and IT equipment reside. This is almost equivalent to building a floor plan and simply placing the equipment into its accurate position on the floor plan. This type of diagramming can be one of the most time consuming methods. When you diagram from a network level you look at the network from the viewpoint of the actual equipment itself. You show a router, you show a WAN link going across into a second router. From the second router you show a connection into a switch. From the switch you show a connection into six more switches cascading off.
WORD DIAGRAMS/EXCEL SPREADSHEETS
Using either Word or Excel to diagram your network is possible. This method let's you document information without needing to purchase a separate application such as Visio. Utilizing Word or Excel allows you to more finely detail the level of information you wish to document than a Visio diagram does.
With this method, you can track server related information such as IP Address assignment, MAC Addresses, server configuration such as WINS and DHCP settings, software installed on the server and much more. The amount of information you track is basically up to you. You can track as much information as you feel necessary. One thing to remember though, try to track as much information as you would need to completely rebuild the server from scratch. Granted, knowing which IRQ the network adapter is assigned to may not be necessary to rebuild a server, but it does come in handy so you can be certain that a rebuild will be 100% identical.
Storing your network documentation in a database essentially serves the same purpose as storing that documentation in a Word document or Excel spreadsheet. However, utilizing a database of some sorts gives you more flexibility and control than any of the above options. For example, using a database, you can maintain a change history of the documentation. This would allow you to essentially snapshot your documentation and then compare the current documentation with past snapshots.
Using this method also brings to light third-party applications that track network documentation. Many call center applications provide this functionality in their products as well.
To summarize, utilizing Visio diagrams, Word documents, Excel spreadsheets, databases, and more are all very valid and common means of documenting your network. However, choosing which method you use is strictly dependant upon you and the requirements you and your company have.
My preferred method, and the method that we employ at the company I work for, is to utilize all three means of documentation. We use Visio to create a physical diagram of our network as well as a network diagram, we use Word and Excel to create detailed documentation of the network servers and infrastructure and we have recently begun utilizing a database through our call center application (FrontRange Software's HEAT) to track much of the server specific configuration information.
Using this sort of meshed-documentation approach gives us the best of all three methods. The major downside though is that it is very time consuming. When users move or major network configurations change, the supporting documentation has to be updated using all three different methods. However, one of the major benefits is that we can ensure that out network is accurately detailed at every different level that we can find. This ensures that we can respond faster and more accurately to incidents than if we didn't have accurate documentation.Ryan Smith