Documentation, and its maintenance, is often a low priority in the day-to-day IT work schedule. That is especially true when the IT staff is maintaining documentation of a living, breathing, ever-changing company network. When the CIO discovers that the documentation is in a poor or nonexistent state, consultants are often charged with the task.
We asked our members to share their favorite low-cost tools for network autodiscovery, an integral part of the network documentation toolbox. They gave us nine suggestions for tools that will uncover every nook and cranny—and hidden device—in your clients’ networks.
Beyond identifying the best tools for a documentation job, we wanted advice on creating and maintaining this information, especially in the case of consultants who are documenting a client’s network. We wanted to answer the following three questions:
- What process should a consultant use to document a client's existing network?
- What methods can be used to keep the documentation up to date?
- Are there "landmines" that consultants should watch for as they work with the client's IT staff to document their existing network?
We asked these questions of industry experts Jeff Miller, product manager for Dimension Data's Surveyor network analysis tools; Mike Nolan, an independent business continuity consultant; and Kendall Hunt, manager of infrastructure services at Tallan, Inc. Here’s what they had to say.
Documenting an existing network
To begin the documentation process, Hunt recommended that consultants find out three key pieces of information:
- What documentation is already available?
- What process—if any—is in place to keep it up to date?
- What documenting resources, such as personnel or software, are available?
“Specific documentation processes depend upon the scope of the network, including the number of sites, location of sites, number of devices, and the complexity of design,” Hunt said.
It’s important to determine the physical access to wiring closets and data centers and the administrative access to devices, Hunt said.
“The consultant needs full access to all network equipment. This means access to lots of restricted areas where networking equipment is stored,” Miller said. “Get all this ahead of time, in addition to securing a client side go-to person, someone who has full access to all locations and equipment.”
Once a consultant has a top-level picture of what resources and level of access are available, documentation can begin with core devices and extend outward as far as desired.
Miller recommends that consultants use a combination of baselining and network analysis tools for automated mapping and configuration collection, coupled with a walk-through visual layout inventory.
“For extra credit, there should be processes that document the desktop hardware and software inventory,” Miller said. “Since there is no ‘perfect’ software application, it's a good idea to spot-check using old-fashioned manual labor—to be sure the documentation is complete.”
To create truly complete documentation, Nolan suggests that it include the following, where applicable:
- The circuit number or IP address
- The prime vendor
- The origination end and the termination end (if point-to-point)
- Data terminal equipment and data communications equipment at each end
- Who in the enterprise owns or has responsibility for the circuit
- How the circuit reaches a building (copper, fiber, microwave, etc.)
- The termination point in a building
- The name and contact number for the prime service provider
“The consultant must verify all the information supplied by the client, with each individual service provider, and make the necessary additions, deletions, and corrections,” Nolan said. “Service providers usually maintain a network map or network diagram of their own for larger clients that they can call up when service is added, eliminated, or when there is a service disruption.”
Keeping the documentation up to date
After taking the time and effort to document the clients’ network, consultants must impress on those clients the need to keep the records updated. If it’s not kept up to date, the consultant’s hard work and the company’s money will have been wasted. Regular updates are the most important part of the entire documentation process and cannot be emphasized enough, Hunt said.
“While software and technology to automate documentation tasks are important as tools, they should not become a crutch or replacement for a strictly enforced change management process,” Hunt said. “While a change management process is seldom always followed in the real world, it can provide a mechanism for forcing documentation to be updated as changes are made and the pertinent information is fresh in the mind.”
There’s no easy answer for keeping network documentation current, according to the experts. Miller suggested that companies repeat the initial documentation process on a regular basis and compare the results with previous collection efforts.
Watch for these landmines
When working with an internal IT department to document a network, Nolan said that a consultant must be careful not to “consider the information supplied by the client as gospel.”
It’s also important to double-check every assumption, Miller said.
Sometimes, a consultant becomes too involved with a client’s system and forgets the main objective of the project. Hunt said consultants should be careful not to getsidetracked into analyzing or questioning the network design or recommending design changes.
“Once completed, the documentation can be used for a detailed design analysis, if needed, and recommendations can be made at that time,” Hunt said. “Of course, potentially harmful security weaknesses that are uncovered should be noted and corrected, and, as always, documented.”
Back it up
Nolan said that it’s important to secure copies of the documentation in case of disaster. He recommended that an electronic version be stored on a server at another physical location. Also, since a major catastrophe could prevent the retrieval of electronic documents, Nolan recommended that paper copies be stored in two locations. And, of course, every change that is made to the network must be recorded in the documentation and backups.