Why You Really Should Have a Backup

I had a bit of a crazy day today with this website, so this is going to be my slightly unconventional post for the week. As you could tell from the title, it’s about why you should really have a backup. From personal experience. (And next week, perhaps I’ll talk about how you can make a backup if you don’t have one.)

I worked on my website a bit this morning; I wanted to post a couple of new things and make some updates to my homepage. As part of this process, I needed to upload a couple of files, which required that I open a terminal window to access the server. No big deal, I do it all the time.

Another thing I needed to do today was pick up in my room/office area. When I took a break from working on my website, I was picking up. I needed to move a desk; the path of the leg was right in the way of the computer, so I needed to turn off the computer to move it out of the way. So I flipped on the monitor, noticed there were two terminal windows open ready for a command, and typed sudo halt in one of them—the command to power down the system.

Then I noticed I’d run it on the server.

You see, Amazon EC2 has this thing where some of your data isn’t guaranteed to stay on the server when it powers off.

I rebooted the server from the management console, but the damage was done—all my posts since May 5th were gone. I panicked, of course, and then I had to go eat lunch. When I got back, I fumbled around in my backups folder and found one from June 9th. Which should have been good, because I’d written all the following blog posts before I left to go camping on the 12th. But after I restored it, there were still five posts missing. Apparently the backup software doesn’t back up posts that are not yet published publicly.

Amazingly, I was able to recover every word of my posts from Google’s cache of my website. (The pictures are missing from the cache, but the links and filenames aren’t, and I still had them on my hard drive.) But searching the internet for your lost data isn’t a very good backup plan. The whole thing wasted me half an afternoon.

And I got very, very lucky.

Only a week ago I overwrote three hours of work by accidentally typing “>” instead of “>>” in a script. It’s amazing how the stupidest user errors can make the worst crashes.

I could have been up and running again in roughly five minutes had I kept a backup that covered everything. Which is why I now have a weekly backup that runs right after I update my website every week. You should too.

How to Clean a CD

I’ve seen a lot of people clean CDs completely wrong. There’s a good reason why most libraries and video rental stores have labels on their discs telling people not to try to clean them—if you do it wrong, you have a good chance of permanently damaging the disc.

There are a lot of ways to clean a CD, but first, here’s how not to clean a CD: Do not rub around the CD in circles. This can cause further scratches. (Furthermore, circular scratches are the most likely to cause permanent data loss, as they wipe out a large amount of consecutive data. Most systems have an error-correction algorithm that can compensate for a small amount of consecutive unreadable data, such as when the disc scratches from the center to the edge.)

Here are two acceptable ways:

  • The simplest way is to take a soft cloth and some CD cleaning solution (lens cleaner is almost the same stuff, and is often advertised as both), spray a bit of solution onto the cloth (I’ve heard that you’re not supposed to spray it on the disc, although I’m not sure why), and rub the CD gently from the center to the outside of the disc. Then turn the disc slightly and repeat. As mentioned above, don’t use any other pattern.
  • Another common method is to run it under the tap and then wipe it off gently (from center to edge, of course), or let it air dry. Some people recommend taking it into the shower, which does essentially the same thing.
Even if you have to use your T-shirt to wipe off the disc because you don’t have anything else handy, please remember: center to edge, not in circles. It pains me to see people rubbing CDs all over their scratchy jeans in random patterns thinking they’re making it better.

If a disc is badly scratched, many people report getting good results by rubbing toothpaste all over the disc, letting it sit for a few minutes, and then cleaning it off. The idea is that you wear off a thin layer of the non-scratched portion of the surface, thus making the scratch shallower. This is not something to try unless the disc doesn’t work anyway and you realize that you might destroy it completely.

Cleaning Your Computer, Part 5: The Case

Your actual computer is the part that usually gets the dirtiest. Fans actually electrically attract dust, which allows them to pull junk into your case at a frightening rate. Since most people never open their computers or even think about cleaning them, the problem usually goes unnoticed. If left alone, the dust can do serious damage by stopping fans, thus causing components to overheat and be permanently damaged. Here’s a quick way to clean out your computer’s case.


  • A can of compressed air. Used to loosen dust and blow it out of fans.
  • A vacuum cleaner. This time the vacuum is essential. If you don’t have one with a crevice tool and can’t borrow one, you might be able to do something with your hands, but it would be a real pain.)

Step 0: Spray compressed air into the fans while your system is running.
This helps to dislodge dust from the fans, as they will blow out the loosened dust. You’ll have to flip the computer around to the back to find a fan on many computers. If you need to, you can disconnect all the cables except the power cable (to avoid possible damage to components that aren’t intended to be unplugged with the power on, switch the computer off, disconnect everything except the power cable, and then switch the power back on).

Step 1: Power down your system and remove the cables.
Take it to a desk or comfortable, open spot on the floor.

Step 2: Clean the power supply fan.
Spray some air in, then vacuum the opening. The power supply fan is next to the power connection, and looks like this:

(Note: The system appears to be plugged in, but that cord is disconnected at the other end.)

Step 3: Clean any other exposed fans.
They’ll look different on each computer, but here’s an example:

Step 4: Open the case.
Find where the case opens. This can sometimes be a bit of a trick. Usually there will be large hand screws on one side of the case, a clip at the top and/or bottom, or a small clip like this one:Once you’ve found the locking mechanism, the side of the case should slide right off.

Before doing anything inside a computer, you should always ground yourself by touching some unpainted metal; the side of the power supply or case is usually a good bet. We’re not planning on touching any components here, but it can’t hurt to be safe.

Step 5: Vacuum out the case, being careful not to touch components.
Spray some compressed air into anything stuck and vacuum out all the dust bunnies. This picture of the inside of the case is tame because I’d recently used it for a demonstration of upgrading RAM and had thus cleaned it out—most people’s will be filled with dust.If you have a Dell computer, that big curvy green piece of plastic is a common feature. It helps channel the heat from the processor heatsink directly into the exhaust fan, thereby avoiding the need for a second fan. You should clean under it by popping it out; it just swings outward when you grab it from the edges, like this:You should also spray some compressed air in the heatsinks, which are those blocks of parallel metal fins (one is in nearly the exact center of the above picture). They help to radiate heat from components that make a lot of it, and it’s very common for dust to get stuck between the fins and reduce their efficiency.

A final target is the vents in the back of the power supply, which tends to get clogged with dust. If the power supply fan stops working, your power supply will quickly overheat and your system is likely to shut down or (worse) malfunction silently. Here’s an example:(Warning: Never open the power supply unit itself if you don’t know what you’re doing with electricity; there are large capacitors in there which can deliver some serious shocks even if the computer is unplugged.)

Be careful not to rub against components with the vacuum; even if you do, it probably won’t damage anything, but better safe than sorry.

Step 6: Put everything back together.
Getting the case back on is sometimes an exercise in frustration—it’s usually much harder than getting it off. With a little persistence, though, you should be able to figure it out.

Cleaning Your Computer, Part 4: Mice

Mice aren’t usually a big problem source in terms of getting dirty, simply because there aren’t many surfaces that stuff can stick to where it won’t immediately rub off. Still, when you’re writing a complete guide to cleaning your computer, it’s hard to ignore the mouse.


  • Rubbing alcohol. Yes, it’s back yet again.
  • Q-tips. No surprises here.
  • A dust cloth or something similar. Some surfaces of mice just need some wiping down; a dust cloth or even a plain old sponge will do fine for this.

And that’s pretty much it. You could maybe find a use for some Cyber Clean, but it’s not really necessary.

Step 1: Unplug the mouse from the computer and/or turn it off or remove the batteries.
If you skip this step, you could look back at your monitor and find you’ve accidentally purchased something useless on eBay. Okay, most of the time it’s not quite that dramatic, but bad things can happen when you’re mousing without intending to go anywhere.

Step 2: Clean the eye.
Nearly all mice today are optical, which means they have a little camera on the bottom. To clean it, just put some rubbing alcohol on a Q-tip and wipe it off. It rarely gets dirty, but it can’t hurt to check.

If you find that your mouse is so old that it still has a ball, unscrew the ring by turning it in the direction of the arrows, pop out the ball, and clean the ball and the rollers (using Q-tips).

Step 3: Wipe down the mouse.
No tricks here, just good old elbow grease. Make sure you don’t drip a bunch of water into the mouse if you’re using water, but otherwise this is all common sense.

Cleaning Your Computer, Part 3: Keyboards

Keyboards seem to be dust magnets (and hair magnets and staple magnets…). Even if you don’t immediately notice the junk accumulating in your keyboard, it has the potential to cause problems with the keyboard—and if you wait for years before doing it, you are likely to have some trouble getting the gook out. And, of course, it’s just disgusting, and a lot of us like to keep things clean.


  • A can of compressed air. This is used to spray air into the corners and loosen up dirt.
  • Some newspaper (a trash can with a large opening works well too). You’re going to want to shake your keyboard upside down to dislodge some of the junk, and you probably don’t want it on your floor.
  • A canister or handheld vacuum cleaner. If you have one, it will come in handy; if you only have an upright, you can do without it.
  • Some Cyber Clean. Once again, it’s not mandatory, but it does come in handy.
  • Two strong paperclips. If you need to remove key caps, this is the safest way to do it.
  • Some rubbing alcohol, a bowl, and some Q-tips. These let you clean between the keys.

Warning about Compressed Air: Since I haven’t had you use compressed air yet, I should take just a moment to point something out: the stuff is not entirely normal air (it would be too expensive to pressurize normal air). While the pressurized chemicals are not dangerous if used normally, you should keep these guidelines in mind:

  • Do not shake the bottle before using (unlike most aerosol products). This is because most aerosols are intended to come out as liquid, but compressed air is not. If you shake compressed air, the product will come out in its liquid form, which is so cold that it can discolor plastics and cause frostbite.
  • Do not turn the bottle upside down. Once again, this will cause liquid to come out. Tilting it a bit is fine, but don’t go beyond 45 degrees.
  • Do not attempt to inhale the contents. (Duh, but people do it.)
  • As with any aerosol product, don’t spray it next to flames or in unventilated areas.
With that covered, let’s get down to business.

Step 0: Unplug the keyboard.
This isn’t difficult, but it is easy to forget.

Step 1: Spray compressed air to loosen dust.
Lift up the Ctrl keys, the tilde key, and the backspace key at the corner and spray some compressed air in (using the little flexible nozzle that usually comes taped to the side of the bottle). Depending on your keyboard, you may need to use a bent paperclip to lift the corner enough to get the nozzle in. This can be a bit of an art at times: sometimes you have to start lifting up the key on a different side than you actually need it lifted and then slide around the edge of the key.

(To get this paperclip shape, just take the central loop and pull it outwards until the angle looks right.)

Step 2: Remove excess loose dust.
Take the keyboard outside or over some newspaper or a large trash can, flip the keyboard upside down, and shake it vigorously. Good whacks on the bottom don’t hurt.

Step 3: Vacuum.
Spray the compressed air in the corners again, then get your vacuum cleaner. (You must plug in the vacuum cleaner before it will work, as I apparently forgot…) If you have the crevice tool handy, that works the best. Push down one row of keys and vacuum toward the gap, then repeat the other way.When you’re done, spray compressed air, vacuum, and shake upside down again. If you don’t have an appropriate vacuum cleaner handy, you can skip this step; using a liberal amount of compressed air and shaking makes a decent substitute.

Step 4: Use Cyber Clean.
If you have some, use it. If you’ve never used it before, it’s easy: just pull it out of the container, stick it on top of your keyboard, and squish it into the spaces.

Step 5: Clean the spaces between keys.
If you didn’t use Cyber Clean or the spaces between the keys still look dusty and/or grimy, moisten a Q-tip with rubbing alcohol and clean between rows. Hold down one key to clean the facing key’s side, then switch to get the other (just like you did with the vacuum cleaner).(Incidentally, this picture was nearly impossible to get, since I only had two hands. It took me four tries and hurt my fingers.)

Step 6: Remove key caps (optional).
Unless your keyboard is really dirty (which it probably is if you’ve never cleaned it before), you should probably skip this step. You should minimize the number of times you pop off the caps, as every time is another opportunity for something to break. If you haven’t cleaned your keyboard in five years or it’s noticeably gummed up, though, it’s worth the bother. (If you’re not sure, try popping off a cap in the middle first, like the ‘h’ key. If it looks reasonably clean underneath, you’re probably good. Also, here’s a picture of what it looked like under the caps after I cleaned using every other step; before it was utterly filthy and filled with dust, although I neglected to take a picture.)Before you begin, take a picture of the keyboard. You may laugh now, but chances are very high that when you go to put the caps back on, you’ll be glad you did—it’s surprisingly difficult to remember exactly where all the keys go, even if you’re a good typist like I am.

Don’t remove long or oddly-shaped keys like the spacebar, shift keys, or return key unless absolutely necessary—many of them have little bars, multiple contact points, or other gimmicks that make them extremely easy to break and extremely difficult to get back on if you don’t break them (see the picture below). Most of the time you can do an acceptable job by removing the rest of the keys and then cleaning under the keys you didn’t remove.a bar under the shift keyTo actually remove key caps, take the two bent paperclips, stick one on each side, and pull them apart. If you happen to have a key cap puller, you can use it, but most people don’t (I actually do have one somewhere, but I couldn’t find it). Be careful when popping them off; most keys are made of pretty thin plastic and are easy to break accidentally. Once they’re all off, you can use any methods you want to clean the remainder of the junk out; I find Cyber Clean works especially well. You can also take this opportunity to wash the caps with soap and water; just make sure you dry them thoroughly before returning them to the keyboard.

When it comes time to replace the caps, place them in the appropriate place (making sure they’re not upside down, which is surprisingly easy to do with some letters like ‘H’) and push firmly on the very center of the cap until it snaps back into place.

Addendum: If you ever spill something on your keyboard…

  1. Immediately flip the keyboard upside down to prevent any more liquid from getting into it.
  2. Unplug the keyboard and remove the batteries (if applicable).
  3. If you spilled something sticky, get a glass of water and dump it on top of where you spilled your drink. Then flip it upside down again as before.
  4. Set a fan on your keyboard and leave it for a few hours. If you have air conditioning and it makes sense to use it, it can’t hurt to turn it on (it lowers the humidity).
  5. Plug the keyboard back into your computer and see if it works. If it works but it’s still sticky, follow these instructions to clean it up. (You’ll probably have to remove the key caps.) If it doesn’t work, you’re probably out of luck. If you have a laptop, the hard drive can probably still be salvaged (so you haven’t lost any data), and the keyboard can often be replaced for a fairly reasonable price if that was the only thing that was damaged.

Cleaning Your Computer, Part 2: Monitors

Most people do not clean their monitors nearly as often as they should (and that includes me). You usually don’t notice the eyestrain you’re getting from staring at dust, spots, and streaks all the time, but it’s still there. Here’s how to clean it up.


  • Rubbing alcohol (LCD screen cleaner or lens cleaner works fine as well if you have some). This is used to wipe down the surface of the monitor. If you’re using a bottle of alcohol, pour some into a bowl so you don’t contaminate the whole bottle.
  • A microfiber cloth (cotton balls work well too). This is used to wipe the dust off your monitor.
 (I didn’t have any cotton balls handy, so I’m just using the cloth this time. The little plastic container is the most convenient bowl-like object I had nearby.)


Step 1: Prepare your computer.
If you get a completely white screen, it will be much easier to see the spots you need to clean. The easiest way is to open a new tab in your browser and navigate to about:blank, which will give you a blank screen. Then press F11, and you should see something like the following.
 You may want to toggle to a black screen a couple of times while you’re in the middle of cleaning; some things show up better on white, while others show up better on black. Of course, getting a black screen is as easy as switching the monitor off.


Step 2: Wipe down the screen.
Dip your cloth or cotton ball in the alcohol or spray it with your lens cleaner. Start by wiping down the whole monitor, then take a closer look for little spots and rub harder on those. If you press very hard at all, the monitor may momentarily warp and discolor around that area; I’ve never seen any permanent damage from this, so I wouldn’t worry about it.


Step 3: Clean around the screen.
I always like to get the edges of the screen too; they collect just as much junk and dirt as the rest of the monitor. You can use the same treatment on them.


Step 4: Try to rub out remaining spots (optional). 
If you still have annoying spots or minor scratches, you might try to use a pencil eraser to touch them up. If you’re happy with how the monitor looks already, don’t worry about it.


Step 5: Wipe down the monitor one last time and dry it quickly.
While some streaks are pretty much inevitable, this does help a bit.
Next week I’ll show you how to clean your keyboard, which is quite possibly the filthiest place in your entire office.

How to Remove a Stuck CD From Your Drive

Ever gotten a disc stuck in your CD drive? It doesn’t happen often, but it can get really annoying. Sometimes rebooting will fix the problem, but rebooting can sometimes take a long time and doesn’t always even work. Here’s an easier way.

Warning: Do not attempt to use this technique if the CD drive is in use! You will very likely damage the drive and/or the CD. If you’re not sure if the drive might be in use, you should first power down the computer. Standby mode is fine, though, which might save you a good bit of time (on Windows 7, you click the arrow next to the “shut down” button to access standby).

To actually eject the disc, all you need is a paperclip. You’ll need to unbend it at least to the first bend, and probably to the second if you have a small paperclip. If you hold a paperclip up to the screen, the extended portion should be at least as long as half the extended portion in this image:

Locate the release hole on the front of the drive and push the tip of the paperclip in firmly as far as it goes. The hole I’m talking about is the little round one above the light.

If you’re lucky, as in the above picture, the drive will pop out enough so that you can grab the tray and slide it out carefully; however, sometimes the drive will stick in a spot where you can’t quite hold onto it. Fortunately, there’s an easy fix: flip the paperclip around and use the other end to pry it out:

Besides removing stuck discs, I use this trick to insert boot discs in computers that are currently turned off; it’s nice not to have to power the system on just to get the CD tray open.