Workshop

un on the server at 9:50 on Monday nights might be causing a problem.
Is it possible to reverse-engineer an undocumented network? Sure, but this requires a good bit of
knowledge. What’s more, it’s really a waste of time if the network is being installed or changed while the
documentation is taking place. See Hour 24, “Reverse-Engineering Somebody Else’s Network,” if you
have a nightmare network that you need to document.
Is this a hint that you should insist on good documentation when you contract out for someone to build a
network for you? Yes! Any professional worth his or her salt will probably be labeling like crazy
anyway, but just in case you run into someone who thinks that an undocumented network equals job
security, you need to get tough. Insist on labels on all cables, and ask for maps. If you have to pay more,
either pay up a reasonable amount, which should be nominal (plus you’ll save time and money in the
long run), or find a different vendor. A lot of vendors are out there, and, ultimately, you’re the person
who either suffers or benefits from the documentation of the network and cable plan.
Summary
You can be the best network troubleshooter in the world, but without documentation, you’re out to sea in
a leaking boat. Documentation can mean the difference between ten minutes of downtime compared to
two hours or so; therefore, a little work up front can really pay off in the long run.
Each type of documentation is important in its own way—for example, labels on cables, maps of the
network cable runs, and functional diagrams of server placement. Also, keeping a logbook can keep
history from repeating itself. In other words, it gives you a point of reference when the network goes
down.
Workshop
Q&A
Q I label cables by number because each cable function can change and it’s time consuming to
replace the cable labels. Is this adequate?
A Not in my experience. Folks don’t always keep track of what numbers are being used, and a number
doesn’t describe what’s at the other end, thus requiring a separate table to translate the numeric cable
number to the physical device (which you’ll have to update when you change devices, anyway). Do
yourself a favor and just put the description on the cable.
Q What should I document on my maps? What shouldn’t I document on my maps?