Networks Are Like Bathrooms
People often misunderstand the difference between networks and computers.
It's common to hear people in offices yell out, "The network is down!" when the problem is something completely different. Let's take a look at how networking is a lot like your bathroom at home. (And no, the answer isn't that it never gets a good cleaning because you're so darned lazy.)
If the faucet drips or the toilet runs, that's not really a plumbing problem. I couldn't tell you the first thing about plumbing, but it didn't take too many nights of listening to drip-drip-drip before I made a trip down to Home Depot and started asking questions. Likewise, just because a computer is hooked up to a network doesn't mean that crashes and annoying behaviors are at all related to the plumbing. If one device in the building is exhibiting a problem but others aren't, it's probably not the network, even if it seems to be. If one computer on the network can't print to a network printer, you won't solve that problem by going into the network closet.
If the faucet suddenly spits out dirty water, let it run a while. Strange things happen with the pipes sometimes. The city works on the water supply, or the apartment complex works on the water heater, and next thing you know, your water looks like Ole Muddy. Just let it run for a while and see what happens. The problem often runs its course. If you can't get to a web site or a particular network server, maybe someone is rebooting it or moving cables around. People do maintenance on a regular basis, and you can't expect everything to be flawless all the time. Wait a few minutes and try again before sounding the alarm.
If you run out of hot water quickly, that's only fixed with money, not elbow grease. You don't have to be a plumber to know that if the first five minutes of your shower are great, but the last ten are icy, there's a big bill coming. You can fiddle with the temperature setting on the water heater, but if you can't fix it in five minutes, you can't fix it with anything but a whole lot of money. Most families would rather plan their showers ahead of time than face the expense of buying a new hot water heater. Likewise, most businesses can put up with a slow network for years rather than face the expense of fixing the problem, because they're afraid of the expense. Making the network admin work an extra day a week won't fix it.
Certain parts of town get really powerful showers no matter what. Houses near the water tower or the water processing plant usually have strong water pressure without doing any special plumbing work. I could hit the nearest water plant with a well-thrown Frisbee, and sure enough, when I turn on my shower full blast, I can strip the paint off a car. If you live out in the sticks, you probably get a trickle. Internet bandwidth works the same way: if your home or office is near a telephone systems building or near an Internet provider, you can usually count on a very fast connection for a very reasonable price. Businesses located in tech-laden skyscrapers can get incredible bandwidth connections very cost-effectively. But if your office is in the boondocks and you need high bandwidth, you're going to have to do some special plumbing.
Changing nozzles won't get you a much more powerful shower. While certain nozzles might help the flow to seem a little stronger, or they might do some fancy pulsating action, they're not going to turn a trickle into a gusher. Likewise, when I plug my laptop into a network, and I don't get the speed I want, I can be fairly certain it's not my network card. Even though I've just got a 10/100 network card, switching to a gigabit card isn't going to make a difference. Network speed is primarily a function of the plumbing, and you can't tack on a cheap fix at the computer side.
That's not to say you shouldn't have good nozzles. We've all gotten into those showers where the water sprays out every which way but loose. The floor gets wet, the walls are soaking, the people in the next room are reaching for umbrellas, but you can't even get the shampoo out of your hair because so little is hitting you. Cheap network cards are like bad shower nozzles: they don't last long, and they have unintended side effects, like high CPU use and buggy drivers. Get a good name-brand network card - they don't cost much more, and they're not glamorous, but they just plain work.
The stuff that matters most is invisible and expensive. Beautiful faucets won't impress anybody if the entire house is running off a ½" garden hose. The real backbones of your plumbing system are the water heater and the pipes running behind the walls and under the floorboard. Those pieces are hard to go back and fix later, so you don't want to make those purchasing decisions without qualified help. If you're not buying this kind of equipment on a regular basis, you don't know the ins and outs of the brands, features, and even the local regulations involved. Network hardware is the same way: the basic plumbing guidelines stay the same, but things change every year, and without help, you can end up buying gear that you can't easily replace later.
Good plumbing requires a lot of knowledge and planning. If you need to water your lawn, you can slap some hose extensions together, scatter some sprinklers around, and turn the faucet on whenever the grass starts to turn brown. But if you want to do a good job, get your lawn looking perfect, and not have to hassle with moving the sprinklers around and manually turning the faucet off and on, you have to do your homework. When it comes time to build a network, you want to research how the pipes work, what kinds of connectors to use, strike a balance between reliability and affordability, and make sure you never have to touch the equipment again. None of that is guesswork.
Don't plan for more bathrooms than you have space for on your property. If you're building a two-bedroom cottage on a two thousand square foot lot, don't waste your money on a water heater that supports a mansion. Sure, you might be able to take it with you when you hit the lotto, but it would make more sense at that point to buy a new water heater. When purchasing network gear, don't purchase gear designed for a company three or four times your size.
Lastly, even the most minor plumbing problem is perceived as an emergency. When somebody can't get hot water to take a shower, they get angry quick. They might be able to make do with cold water, but they're not happy about it, and they proceed to tell everybody they meet about what a lousy morning they're having, and how the landlord better fix it or there's gonna be trouble. When a user is having a network problem, they yell and pull their hair out. Problems from "I can't print on the network!" to "I can't see last night's sports scores!" are all spoken with the same urgent tone of voice, and everyone always expects the network administrators to drop everything immediately.
Brent Ozar is a HAL-PC member, web developer and network admin. He lives with his girlfriend, two turtles, and the sad knowledge that he will never kick his coffee habit. He can be contacted at email@example.com.