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Web App of the Week: ScreenToaster

David Murphy — Thu, 19 Nov 2009 18:10:45 -0600

Ever have one of those moments? You know the one: When it's so difficult to teach someone how to accomplish an everyday task in a particular application that you up and grab the keyboard and mouse yourself and just get 'er done, as it were. Isn't that frustrating? Doesn't your passionate rage for simplifying the art of attaching files to email terrify your coworkers, friends, and loved ones? Wouldn't you like a better way to show someone how to accomplish desktop tasks, one that doesn't actually require you to get up from your chair or, better yet, even pick up a phone?

In a move that's sure to sooth the savage beast that's been identified as a computer expert by his or her flock of advice-seeking peers, the Web app ScreenToaster is a perfectly packaged solution for showing people how to get stuff done on a PC. It does this by taking a live video (complete with audio, if you so choose) of whatever it is you're doing on your desktop, straight out of your Web browser--no additional software installation is necessary, save for a requisite click on the "accept" button for a piece of Java.

But surely the app can't be just that easy? There has to be another catch! Only, there isn't. You don't have to sign up for the Web app in order to use its recording functionality, which is ideal for those that want to give things a test run before spending time crafting the perfect how-to video. You can even select what portions of your desktop you actually want to record--ideal if you don't want your coworkers to see you surfing Maximum PC in a side window. When you're finished with your masterwork, merely create an free account on ScreenToaster to unlock the service's distribution features.

With but a click of the mouse and a few extra keystrokes, you can save a Flash-based version of your video on either ScreenToaster's site or YouTube. You can also download your movie as a .mov or .swf file, which is especially useful for those who want to keep an offline archive of their video advice for future use.

Every Thursday, Maximum PC picks a new Web App as its favorite of the week. Have a Web App that you can't live without? Twitter David Murphy @acererak with your latest suggestions.

How to Build Your Own 3D Camera Rig for Under $20

Eric Kurland — Wed, 18 Nov 2009 23:00:00 -0600

How Does Stereoscopic 3D Photography Work?

Stereoscopic 3-D photography has been around almost as long as photography itself. In the 1830s Sir Charles Wheatstone theorized that we see the world in three dimensions because our eyes are set about 2.5 inches apart, and see from two slightly different viewpoints. You can test this by holding your thumb at arms length. Close one eye and look at your thumb, then look with just the other eye, and you will see that there is a deviation, or parallax, between what your eyes see. Your brain fuses these two views together, interpreting the amounts of parallax as depth. This is called binocular stereopsis.

Wheatstone figured out that two cameras could be placed side-by-side and take simultaneous pictures, creating a pair of photographs from both left eye and right eye perspectives. When viewed through a stereoscope, the left eye only sees the left image, the right eye only sees the right image, and we perceive a single 3-D view.

The author's 3D photos from Comic-Con

Throughout the late 19th and early 20th centuries, stereo photos were all the rage, with many thousands of stereo cards produced. In fact, many Victorian era homes kept a stereoscope as the centerpiece of their living rooms - sort of the entertainment center of the day. Still, the process of making 3-D images was very complicated, as it was necessary to have two synchronized cameras to take the pictures, and quite a bit of skill to align and mount the finished prints or slides for viewing. Over the years, a number of film cameras have been made with dual optics and shutters, specifically for stereography, but these still require a great deal of meticulous work by the photographer in order to properly align pictures for display.

Do-It-Yourself 3D

The 21st century has seen a resurgence in the popularity of stereography, or 3D imagery, and thanks to the availability of inexpensive digital cameras and photo-processing software, do-it-yourself 3D imagery is now possible.

The simplest method for taking a 3D photo requires just a single camera, and a stationary subject. Place your feet firmly on the ground, with your weight on your left foot, and take a picture. Shift your weight to your right foot and take a second picture. You now have a stereo pair of images, one for the left eye and one for the right eye, which can be viewed in 3D. Obviously, this technique, called “sidestep” or “cha-cha” 3D, only works for subjects that are not in motion.

To take stereographs of dynamic subjects, we will need to take two photos at exactly the same time. Japanese camera manufacturer Fuji recently released the first digital camera equipped with two lenses for 3D. Of course, for the technologically savvy, you can make your own 3D camera rig using common building materials and two digital cameras.

For this project, we’ll use a pair of matching Canon PowerShot cameras and specialized synchronization software called StereoData Maker, or SDM, which is a nonvolatile firmware upgrade based on CHDK, the Canon Hack Development Kit. SDM adds a set of features to certain Canon cameras, specifically for the taking of 3D pictures.

What You Need

Two Canon PowerShot cameras compatible with SDM (Buy them here)
Two 4GB SD cards
Two right-angle metal brace clips
Two tripod screws or 1/4-inch thumbscrews
Cloth tape or sturdy electrical tape
Metal washers
Two USB cables
Altoids tin
Push-button switch (Buy them here)
Two female USB connectors
Battery holder
Three 1.5V AAA batteries
Hot-glue gun
A Dremel tool
Red/cyan 3D glasses (Buy them here)

Aside from the digital cameras and tools, the core components of the rig won't cost you more than $20! Now it's time to assemble the pieces.

Step 1: Load the SDM Firmware

First, you will need two Canon PowerShot cameras (they don’t need to be the exact same model) and the corresponding StereoData Maker firmware. While SDM isn’t available for all Canon PowerShot models, it does work on a wide variety. A full compatibility list can be found at the Stereomaker.net website. Scan the list for your cameras and download the specific firmware and common_files.zip for each. Unzip both archives to the same directory.

SDM comes with a simple installer program that will format your SD cards and install the SDM files. Run the sdminste.exe executable, insert one of your SD cards into a card reader on your PC and click “new install.” Select whether this flash card will be for the left or right camera and click OK, then follow the onscreen instructions for formatting. Do the same for the other card. Make sure to note which card is for the left camera and which is for the right.

Slide the physical write-protect tab down on the SD cards and insert each into the proper camera. The firmware only loads from the cards when they are in the “locked” position, but the cameras are still able to write photos to them normally.

Step 2: Build the Mounting Rig

The next step is to mount the cameras in a side-by-side orientation. Some hobbyists sell specialized 3D slidebars for two cameras online, but you can make your own. This can be as simple as drilling two holes in a wood ruler and bolting the cameras down with 1/4-inch thumbscrews.

Ideally, you want the lenses of your cameras as close together as possible—about the distance between two human eyes. The best way to do this is with one of the cameras turned upside down. To mount the cameras in this way, we will build something called a z-bar with two right-angle truss clips or braces, which you can buy at any hardware store.

Align the sides of these two bars and fasten them together using heavy cloth tape, leaving the holes along the base exposed. With 1/4-inch thumbscrews, mount a camera onto each clip, using metal washers on each side of the base to make sure you get a tight, level fit. Position the cameras so that the centers of the lenses are as evenly aligned as you can make them. Don’t worry if the alignment isn’t 100 percent perfect, as we can correct the images later in software.

Step 3:Build the USB Switch Remote

One of the functions added by StereoData Maker is synchronization of the cameras’ shutters via a 5-volt pulse sent through their USB ports. This requires that a battery-powered switch be attached to both cameras via USB cables. The Stereomaker.net website contains several varying schematics for this synch controller circuit.

The simplest to assemble uses a pair of USB connectors with both pins 1 wired to a button, and both pins 4 wired to a negative battery terminal. The batteries’ positive terminal connects to the other contact on the button, so that when it is pressed, it completes the circuit to both cameras. The cameras need to receive a 4.5- to 5-volt pulse, so you can use a combination of three 1.5V AAA batteries.

You can build this circuit into any small enclosure, such as an Altoids tin, which has a hinged lid for easy access. We found female USB connectors, battery holders, soldering supplies, and push-buttons online at Allelectronics.com.

Cut openings into the side of the Altoids tin to fit the two USB ports and glue the ports in place. Drill a hole in the face of the enclosure for the push-button as well. On the battery holder, connect the positive battery wire to one contact on the button switch, and carefully solder the negative battery wire to pin 4 on both USB ports. Solder a short wire from pin 1 on both USB ports to the other contact on the button. You can use the USB cables that are supplied with the cameras to connect them to your synch controller. Alternatively, you can hardwire USB cables to the controller in place of the connectors. If this step seems too daunting, there are links on the StereoData Maker website to sources that sell pre-assembled USB switches.

Step 4: Shoot Your Photos

Once you have the hardware assembled and the StereoData Maker firmware installed onto the SD cards, you are ready to start shooting 3D pictures. Power up both cameras and wait for the SDM splash screen to appear. You can access the SDM menus by briefly pressing the “direct print” button to put the camera into <alt> mode, followed by the menu button.

The SDM menus contain numerous options for both beginners and more advanced stereo photographers. For now, we will just check to ensure that the USB synchronization is turned on. Make sure that any settings you adjust on the left camera are also changed on the right camera. Press the “direct print” button again to exit the SDM menu.

The left photo

You can now set your cameras up as you normally would to take a photo, adjusting the ISO, shutter speed, and aperture identically on both cameras. Press and hold the button on your USB switch to auto-focus. When both cameras are ready, their blue LEDs will light up. Release the USB button and both cameras fire simultaneously, capturing your stereo pair.

A general rule of thumb for taking good 3D photos is that the distance between the rig and your subject should be at least 30 times the distance between your two lenses. In other words, if your lenses, measured from center to center, are 2.5 inches apart, you should be at least 75 inches, or about 6 feet, away from your subject.

The right photo

Step 5: Process Your Photos

Now that you have taken a pair of images, it’s time to look at them in 3D. To do this, the two images need to be aligned and put into a format suitable for 3D viewing. While this can be done with general image-processing programs such as Adobe Photoshop, most stereographers prefer a specialized freeware application called StereoPhoto Maker.

Begin by downloading and installing the StereoPhoto Maker program. Remove the SD cards from your cameras and copy the contents onto your PC. We recommend organizing your files into subdirectories for left and right images to make it easier to keep track of them. Run the StereoPhoto Maker program and under the File menu, select “open left/right images.” A dialog box will open, asking for the left image. Browse to the folder with the left photos, select a file, and click Open. Do the same for the right-side image, selecting the corresponding picture from the folder with the right-side images. The program will open both files and show you the two pictures side-by-side.

Under the Adjust menu, select “auto color adjustment” to match the tone of the two images. Next, select “auto alignment,” and StereoPhoto Maker runs an algorithm that corrects for misalignments between the cameras, and sets the stereo window based on the nearest point in the shot. Once the auto-alignment is finished processing, you can put on your red/cyan 3D glasses, select a color anaglyph mode from the Stereo menu (we prefer Dubois anaglyph, for its color correction), and marvel at the depth in your 3D photo.

If you would like to make more advanced alignments, you can select the easy adjustment mode, and do manual corrections as needed. StereoPhoto Maker will allow you to save your pictures as anaglyphs, parallel, or cross-view pairs, and will even print out a vintage-style stereo card for your Victorian stereoscope.

Additional Resources

Stereo Club of Southern California -- The Los Angeles–based 3D club offers 3D tutorials and information on 3D photography on its website.

3-DIY.com -- The author's website on do-it-yourself 3D.

Complete Guide to Troubleshooting USB Problems

Mark Edward Soper — Wed, 18 Nov 2009 15:30:00 -0600

The "U" in USB stands for "Universal", and no other I/O port does so much for so many computer users as USB. From providing a home for keyboards and mice to driving printers, scanners, all-in-one units, and providing access to terabytes of storage and the Internet, USB ports do it all. That also means that USB-related problems can cripple your PC, leaving it unable to access storage, input, and output devices.

Tracking down the causes of USB-related woes can be difficult, but in this article, we show you the common and uncommon causes for USB problems – and their solutions.

USB Troubleshooting 101

Recent operating systems include drivers for common USB devices, such as keyboards, mice, and storage devices. If one of these devices is not recognized when you plug it into a USB port, try another USB port on the computer itself (we'll discuss troubleshooting ports built into hubs later), preferably a USB port built into the port cluster on the rear of a desktop PC.

If the device works in some USB ports, but not others, note the ports that are not working. This information will be used to help determine if the cause is the hardware setup at the BIOS level or at the Windows driver or Device Manager level.

If the device works on another PC, but not on yours, the problem lies with your PC. However, if the device doesn't work on any PC, it's time to replace the cable, or the device itself.

Even if you never have a USB device that doesn't work at all, you might see one of the following messages when you plug a USB device into your computer or into an external hub:

"This device can perform faster"

To solve this problem, we need to see how USB ports are configured in the system BIOS – and find out what type of USB hub is in use.

"Hub power exceeded"

This problem, on the other hand, requires a trip to the Windows Device Manager.

Diagnosing USB Port Problems in BIOS Setup

BIOS setup is the place to check if you have any of the following USB problems:

- Your system doesn't recognize a mainstream USB device, such as a printer, mouse, or storage device, in any USB port.

- You get a "This device can perform faster" error message when you plug a Hi-Speed USB (aka USB 2.0) device into any port on a recent computer.

- You can use a USB drive for storage, but you can't boot from it, and you've verified the drive is a bootable device.

- You can use a USB keyboard in Windows, but not for accessing the BIOS at system startup.

To check BIOS settings, restart your computer and press the appropriate key to open the BIOS setup menu.

Tip: If you are unable to access the BIOS setup menu with a USB keyboard, plug in a PS/2 (6-pin DIN) keyboard (if your system has a PS/2 keyboard port). It's worthwhile keeping an old PS/2 keyboard around for troubleshooting. Some USB keyboards can also be adapted to PS/2.

Checking for "Missing" USB Ports in BIOS Setup

Once you have the BIOS settings menu open, what's next? Typically, you will find USB port settings in the Integrated Ports or Integrated Peripherals menu:

If the USB controller or host controller is disabled, no USB ports will be recognized by Windows, and consequently no USB devices will be recognized either.

What if some USB ports are usable, but others are not? Some systems enable you to specify the number of USB ports in BIOS setup.

To solve problems with "missing" USB ports, make sure the following settings are enabled:

USB controller

USB 2.0 controller (aka USB EHCI controller)

USB legacy support

Save changes, exit BIOS setup, and your system will restart, providing access to USB ports.

Tip: If you are unable to use a USB keyboard in BIOS setup, but it works after Windows boots, there's a problem with USB keyboard or legacy support. Change the setting, or contact your system or motherboard vendor for a BIOS update.

Missing USB 2.0 Support

USB 2.0 support has been included in virtually all systems built in the last five years or so. However, it's possible to configure a system so USB 2.0 support is disabled.

On most systems that include USB port options in the system BIOS, you can specify whether to run USB ports in 1.1 or 2.0 (Hi-Speed USB) modes. Depending upon the system, you might see separate entries for USB controller and USB 2.0 controller in BIOS setup, or BIOS setup might have a single entry for USB controller with the option to enable 1.1 support only or 1.1/2.0 support.

Make sure USB 2.0 support is enabled, save changes, exit BIOS setup, and your system will restart, providing USB 2.0 support.

Note: If you have an old system that was never updated to Windows XP SP1 or later, its USB 2.0 ports will run only in USB 1.1 mode, regardless of the BIOS setting, until SP1 or later is installed (SP1 added USB 2.0 support). So, if you're reinstalling Windows XP original edition, make sure you install SP3 immediately, if not sooner (see our article on using the free nLite utility to do this).

Diagnosing USB Power Management Problems

Some systems cannot wake up a system from S3 (deep sleep) power management mode unless this option is enabled in the system BIOS. If you are unable to wake up your system by tapping on a USB keyboard or moving the mouse, make sure this option is enabled in the system BIOS.

Diagnosing USB Problems with Device Manager

If you're still having problems with some USB ports after making sure that the BIOS settings are correct, the next stop for Windows users is Device Manager.

In Device Manager, USB 2.0 controllers are listed as Enhanced, while USB 1.1 are listed as OpenHCD. Note that a single USB 2.0 controller can manage all USB ports built into the motherboard, while each root hub requires its own OpenHCD controller.

Note: If your system does not have USB 2.0 support enabled in the BIOS, an Enhanced controller entry will not appear in Device Manager.

Root Hubs and Generic Hubs

You won't find USB ports listed by that name in Device Manager. Instead, Device Manager lists USB ports by host device:

- Root hub

- Generic hub

Root hubs host USB ports connected to the computer's motherboard or add-on USB host adapter card. A root hub typically hosts two USB ports in 1.1 mode, and the root hub on a system with USB 2.0 support hosts all of the USB ports built into the system. To determine the number of ports a root hub hosts, open a root hub's properties sheet in Device Manager and click the Power tab.

If a root hub is disabled in Device Manager, devices connected to the hub cannot be used and are no longer displayed in Device Manager.

To enable a disabled root hub, right-click the hub and select Enable from the right-click menu. Follow any prompts displayed to complete the process.

Generic hubs are external devices that host USB ports. A generic hub plugs into a USB port, enabling the port to service multiple devices. By daisy-chaining generic hubs to a root hub, a single USB port can support up to 127 devices.

Generic hubs are available in a variety of forms, from standalone devices that include four or more USB ports to keyboards and monitors that include USB ports. Because some generic hubs are self-powered, and some are bus-powered, generic hubs can cause power problems for some USB devices.

Hubs and USB Power Problems

One of the most poorly understood causes of USB problems is the difference between self-powered and bus-powered hubs. Self-powered hubs include root hubs (which draw current from the computer's power supply) and generic hubs that are connected to AC power. These hubs provide 500mA of current to each USB port.

Generic hubs that do not have an AC power source are bus-powered, and provide only 100mA of current to each USB port.

Bus-powered hubs are suitable hosts for USB devices that use little power, such as keyboards, most mice, printers, and external hard disks that use AC power. However, device power requirements vary widely, and other types of popular devices, such as portable hard disks, flash memory drives and card readers, and game controllers with force feedback often cannot operate when plugged into a bus-powered hub.

To determine the power requirements for any USB device, open the Power tab for the root or generic hub the device is plugged into.

The devices shown in this example must be plugged into a self-powered USB hub, as they require more than 100mA of current.

However, the devices shown in this example can be plugged into either a bus-powered or self-powered hub, as they require less than 100mA of current.

Dangers of Exceeding Available Hub Power

If you plug a device that requires more power than the hub can provide, what happens?

If you plug a device that requires more than 100mA of current into a bus-powered hub, you will see a "Hub Power Exceeded" message.

Click the message to see a listing of other ports that you can use.

While the listing isn't specific, keep in mind that any built-in USB port is connected to a root hub, and will therefore provide 500mA of power – enough for almost all devices.

What happens if you plug a device that requires more than 100mA of power into a self-powered hub that becomes disconnected from its AC power supply? At that point, the hub becomes a bus-powered hub, the voltage per port drops to 100mA, and, if you have a flash drive plugged into the port, you might destroy it.

To avoid disaster, consider this advice:

- Think twice before using a bus-powered hub.

- If you use a bus-powered hub, make sure you know the current requirements for all USB devices you plan to use with the hub. Any device that requires more than 100mA of current will not work with a bus-powered hub.

- If you're worried about forgetting to check current requirements before you plug in a new device, use a self-powered hub.

- If you already have a bus-powered hub and are frustrated because some devices will not work with it, replace it or connect the hub to a compatible AC adapter.

Hubs and USB Performance Problems

Most, but not all, USB generic hubs sold today support USB 2.0 speeds – but there are innumerable USB 1.1-only hubs still in use. If you plug a USB 2.0 device into a USB 1.1 hub, you will see the same "This device can perform faster" error message you would see if you had plugged the device into a USB 1.1 port on the computer.

How can you tell how fast a USB hub will run? There are two methods I use:

- Check for markings on the hub

- Check the properties sheet for the hub

Most USB 2.0 hubs are labeled as such. However, an unlabeled hub might also support USB 2.0 speeds.

To determine the speeds supported by a USB hub, follow this procedure:

1. Plug a USB 2.0 device, such as a storage device or wireless adapter, into one of the ports on the hub.

2. Open Device Manager.

3. Expand the Universal Serial Bus Controllers category.

4. Open the properties sheet for the hub.

5. Open the Power tab and look for the device you connected in Step 1.

6. Repeat steps 4-5 until you find the correct hub.

7. Open the Advanced tab and note the hub's performance level. A hub that supports USB 2.0 speeds will run at high-speed. A hub that supports only USB 1.1 speeds will run at full-speed.

Note that some desktops with front-mounted USB ports run these ports in USB 1.1 mode only.

USB Hub and Device Power Management Problems and Solutions

By default, USB root and generic hubs are configured to enable the PC to turn off the device automatically to save power. However, USB devices are configured by default to enable the device to wake up the system.

If your system cannot be awakened from standby, check these settings, as well as the power management settings in the system BIOS.

Cables and USB Device Compatibility

USB cables not made for high-power (over 100mA) devices can cause those devices to fail. Typically, thicker cables (such as the white cable shown below) use 28AWG cable, which is capable of carrying full power to any USB device, while thinner cables (such as the gray one shown below) use thinner cable of unspecified gauge. Smaller-gauge cable prevents full power transmission to the device.

While using an underperforming USB cable won't cause the device to be damaged, it can be frustrating to need an extension or other cable doesn't work with some devices.

The second factor is the rise of alternative device cable connections. At one time, virtually all USB devices, with the exception of digital cameras, used the standard B cable connector. With most current devices, except for printers, the standard B connector has been replaced by the five-pin mini-B cable. And, some devices use four-pin mini-B cables or Mini-A cables. To be prepared for any eventuality, consider keeping a universal USB 2.0 cable handy (like the one in the photo below).

The third factor is the need to exceed 500mA at startup with some portable USB hard disk drives. Some onboard USB ports are capable of proving more current to spin up these drives, while others are not. Keep in mind that self-powered generic hubs typically cannot provide additional power for these drives.

If you cannot use a single USB cable to provide sufficient power with some systems, use a double-headed cable. One connector provides power and data services from a single USB port, while the other provides additional power from a second USB port. Some portable hard disk vendors supply this type of cable, while others make it an extra-cost option.

USB Driver Problems and Solutions

Because recent versions of Windows recognize standard USB devices such as mice, keyboards, and storage devices without the need to install drivers, it's easy to forget that a plug-and-play installation is possible only when the computer has the appropriate driver already installed.

If you plug a USB device into a computer that does not already have the appropriate drivers installed, you will be prompted to run the Found New Hardware Wizard.

Continue only if the installation instructions for the device recommend doing so. In most cases, however, you need to run the device installation program provided on the device's driver CD before Windows can install the device. In such cases, click Cancel, disconnect the device, and install the driver for the device first.

Once the device is installed, you might be able to update the drivers with the device's Driver tab on the properties sheet in Device Manager.

Conclusion

Want to avoid having USB problems at all? Here are some best practices that you should follow to get your ports in order.

- Make sure your computer is configured to run USB ports in USB 2.0 mode

- Upgrade systems running original Windows XP to SP1 or greater

- Avoid using bus-powered USB hubs with most bus-powered peripherals other than mice, keyboards, and some types of game controllers

- Avoid using USB 1.1-compatible hubs with USB 2.0 devices such as storage, printer, scanner, and multifunction devices

- Use the Device Manager properties sheets for USB ports and devices to solve problems

- Make sure you install driver software for new USB devices before you connect them to your system

- Replace USB cables not designed for high-powered devices with thicker USB 2.0-compliant cables

- Check power management settings in BIOS and Device Manager for USB ports and devices

Mark Edward Soper is the co-author of the new book CompTIA A+ 220-701 220-702 Cert Guide, with Scott Mueller and David L. Prowse (Pearson).

20 Essential Tricks and Skills Every BitTorrent User Should Know

Paul Lilly — Wed, 11 Nov 2009 17:30:00 -0600

Every week, we're going to spotlight a popular program or service and show you how to grab hold of the reigns and get the most out of what you're doing. We already kicked off the series with guides to tweaking Outlook and Firefox, and today we turn our attention to BitTorrent.

BitTorrent, as you're probably already aware, is a decentralized peer-to-peer file sharing protocol ideal for transferring large files (and if you didn't know that, don't worry, we also include some lightweight tips to get you started). In a nutshell, the way it works is when you're downloading a massive file -- like a Linux distribution, for example --bits and pieces of the file will be uploaded at the same time. Typically BitTorrent allows for a more efficient and faster transfer method than traditional, Direct Connect P2P software.

To get started, you need a desktop client. We recommend using uTorrent, or uT for short. We prefer uTorrent based on its combination of advanced features, performance, and small footprint -- in other words, it has all the makings of a power user program.

On the following pages, we'll not only show you how to get the most out of uTorrent, but out of BitTorrent in general. We'll cover both basic and advanced tips, and then toss in some of our favorite third-party add-ons for good measure. Whether you're new to BitTorrent or a seasoned vet, there's something in this guide for you.

Know the Lingo

Before diving head first into the world of BitTorrent, take some time to familiarize yourself with the protocol's language. For example, do you know the difference between a tracker and a leecher? Why are leechers frowned upon, and how can you avoid becoming one? These are just some of the terms you'll need to know as you traverse the BitTorrent universe. Here's your handy cheat sheet:

Image Credit: lili.org

Torrent: Lazy linguists sometimes substitute Torrent in place of BitTorrent, but it actually has a definition all its own. A torrent is a small metadata file usually just a few kilobytes in size. It contains information about the file(s) you're trying to download, such as file names, file sizes, where to download, and so forth. The torrent file (.torrent) is not the actual data you're trying to retrieve.

Peer: Any other computer on the Internet which is both downloading and uploading portions of a file at the same time.

Leech(er): There are two meanings for this one. The most common definition of a leech is someone who disconnects and stops sharing a file as soon as they've obtained a complete copy. The fewer people there are sharing a file, the longer it takes to download, and for this reason, leeching is highly discouraged.

Peers who haven't finished downloading a file are also referred to as leechers, but not necessarily in a derogatory way.

Seed(er): It's good etiquette to continue sharing a file even after you've finished downloading the entire torrent, if only for a short while. This practice is known as seeding.

Reseed: When no more seeds exist for a particular file, then anyone who was actively trying to download it will be unable to finish. A reseeder is someone who has the completed torrent, reconnects to the swarm, and saves the day.

Swarm: Any group of users connected to each other for downloading and/or sharing a particular file.This includes peers, seeds, and leeches.

Tracker: A central server which stores the torrents, coordinates the action of all the seeders, peers, and leechers, and manages the connections. The Pirate Bay (TPB) is the largest tracker on the Internet and often the center of media attention due to ongoing legal issues. Not all trackers are public; there are several private trackers which require a membership.

Share Rating / Ratio: This refers to the ratio of uploaded data divided by downloaded data and is applicable only for the current session. A share rating of 1.0 means you've uploaded the same amount of data as you've downloaded.

Where to Find Torrents

Let’s address the 900lb gorilla right off the bat. Not everyone uses BitTorrent for, ahem, legitimate reasons, and for them, there are plenty of less scrupulous tracking sites littered all over the Web. You know the ones, because they’re usually tangled in high-profile legal proceedings. Let us be clear: We don’t condone software piracy, even if we don’t’ always agree with the DRM measures paying customers have to put up with.

So where you can find legal torrents? As it turns out, there are a handful of resources serving up free and unrestricted content. These include:

• www.legaltorrents.com – specializes in “high quality open-licensed (Creative Commons) digital media and art.” Several membership tiers are available, including one that’s free and comes with unlimited access to all content and custom feeds by email and RSS.

• www.legittorrents.info – a no fuss tracking site serving up a variety of free and legal torrents ranging from Podcasts to Release Candidate software.

• http://linuxtracker.org – just like it sounds, this is the go-to tracker for all things Linux.

• www.publicdomaintorrents.com – deals entirely with films that are no longer copyrighted, many of which come optimized for mobile devices.

• http://bt.etree.org – an awesome resource for music lovers, bt.etree includes a ton of live concert recordings from trade friendly artists.

In addition to dedicated torrent sites, many software publishers -- especially in the Linux community – include torrents in their downloads section. In many cases, you’ll find it’s much faster to download a Linux distro or mammoth game demo by downloading via BitTorrent instead of HTTP.

Manage Torrents Remotely

One way to access uTorrent from a remote location is to install a desktop login client like LogMeIn, which gives you access to your PC through a Web interface. But if you're only interested in controlling uTorrent while away from home and not your desktop, there's a way you can do that. After installing and configuring uTorrent's WebUI, you'll have access to all of your BT downloads along with the ability to add or remove torrents. Here's how to set it up.

Download the latest version of WebUI from here (see here if the download link is broken). Bear in mind that this is a beta release, meaning instability could rear its ugly head, although we never ran into any problems. Rename the downloaded file to webui.zip.

We need to place the webui.zip file in the same location as uTorrent's settings.dat file. In Windows 7, navigate to C:\Users [USERNAME]\AppData\Roaming\uTorrent. In earlier versions of Windows, the correct path should be C:\Documents and Settings\[USERNAME]\Application Data\uTorrent. If you can't find it, or the directory doesn't exist, perform a search for settings.dat.

If you're running a portable version of uTorrent (and we'll show you how do that later), you'll find the settings.dat file in the uTorrent.exe folder.

The next step is to enable WebUI in the uTorrent client. Go to Options>Preferences and you should now see a WebUI entry. Click on it, then put a check in the Enable WebUI checkbox. Enter in a username and password and check Enable Guest account with username. Hit Apply, but don't exit out just yet.

If you don't remember the port number you used to configure port forwarding earlier, go back into the Connection tab and make note of it once again. We're going to need this in the next step.

Let's test out if you followed the steps correctly. Open up your browser and type http://localhost:PORT/gui/ and substitute the port number from above where it says PORT. Once you enter in your username and password, you should be in the WebU's interface.

Of course, the whole point of this is to manage your BT downloads from a remote location and not from the same PC you installed uTorrent on. You'll need to know your IP address, which you can retrieve from sites like WhatIsMyIP.com and myIPaddress.com. Use your IP address to login remotely, substituting it in place of localhost. So for example if your IP address is 12.34.56.789 and the port you recorded earlier was 12121, you would type in http://12.34.56.789:12121/gui/.

Note that this isn't likely to work by trying to access your client PC from within your home network. Instead, you'll need the IP address assigned by your router. For example, http:192.168.1.133:12121/gui/. You can find your PC's internal IP by opening up the Command Prompt (Start>Run>CMD) and typing ipconfig. Make note of the IPv4 Address.

Make Your Own Torrents

Wondering how you're going to send that HD video you took of your vacation to family and friends? Or what about all those pictures you snapped at the LAN party last week? For these and other situations where you're dealing with large files, or a large collection of files, BitTorrent can be the best way to distribute them to others, provided you're dealing with an at least a semi computer-savvy bunch (in other words, you may want to just burn and send Aunt Mabel and Uncle Fred a DVD).

Creating a torrent isn't at all complicated and is probably much easier than you think. If you're using uTorrent -- and we recommend you do -- go to File>Create new Torrent, or mash CTRL+N.

In the pop-up window that appears, click the Add File button if you're dealing with a single file, or Add Directory if you have a folder full of files you want to share. Next you need to pick out an active tracker. A website called the Beehive maintains a list of active trackers that have been checked every 24 hours, and you can reference that list here. Once you have a tracker picked out, copy and past the URL into the Trackers box. Next, click the Start seeding checkbox, and press the "Create and save as..." button.

Before you can share your torrent with anyone, you first need to upload it to whatever torrent tracking site you picked out earlier. Most tracking sites require that you register with them before you're allowed to upload. Once you've done that, navigate to the site's upload section and add your torrent.

Now all that's left is to share your torrent with your friends and family. You can use the link provided by the tracking site, or just email the ultra-small torrent file, which should only be between 10KB to 20KB. Don't forget to seed!

Hire Others to do Your Heavy Lifting

BT downloads put a heavy strain on your Internet connection and can saturate both your upstream and downstream bandwidth. But there's an alternative to using BitTorrent the traditionally way.

There are several sites wiling do the dirty work for you and download the torrent data right to their servers, at which point you can access it just like any other HTTP download. Furk.net is one such example and offers free access to several already-hosted torrents. For a fee, Furk.net will let you upload torrent, download multiple files at the same time, uncap your download speed, and some other perks. If a BitTorrent client isn't an option, this is the next best thing.

Prioritize BitTorrent Traffic

With BitTorrent downloads and uploads barreling through your Internet connection at full bore, you may find that your speedy broadband connection has been saturated, reminding you of what it was like surfing the Web on a 56K modem. Ideally, BT traffic would run blazing fast when nothing else is going on, but yield to everything else. That's where your router's QoS (Quality of Service) settings come in.

Image Credit: techimo.com

Open up your browser and type 192.168.1.1 in the address bar. Enter your username and password when prompted (consult your router's manual if you don't know what this is). Once inside your router's GUI, click on Applications & Gaming>QOS. Click the Enable radio button , and then scroll down to the first blank box titled Application Name. Type uTorrent, Azureus, or whatever BT client you're running. Set the Priority to Low or Lowest and enter in the port number as configured in your BT client. HIt save and exit.

Some routers offer more fine grain QoS control than others, and certain third party firmware -- like Tomato -- offers a plethora of tweaking options. Getting into the intricacies of QoS settings goes beyond the scope of this guide, but if the options are there to play with, try experimenting with different settings.

Kickstart Downloads that Stall at 99 Percent Finished

Remember that scene in Happy Gilmore where Adam Sandler yells at his golf ball, "Why don' you just go home? That's your home! Are you too good for your home?," right after narrowly missing a putt? That's the same frustration you'll feel after investing an afternoon to downloading a mega-sized torrent, only to have it hang at 99 percent complete. So close, and so maddening!

Image Credit: D-Link

There are a few reasons why this might happen. If you own a router with a Game Mode, it could be scrambling the packets so that your torrent fails the hash check. It's a bit more technical than that, and it's pretty rare for this to happen, but it does occur. Try disabling your router's Game Mode and see if the download is able to finish.

The person who created the torrent may have inadvertently included a hidden system file -- thumbs.db, for example --which can prevent your download from reaching 100 percent. In other cases, the stubborn file could be corrupt, and it may be something you can do without, such as a readme.txt file. To see which file is causing all the commotion, click on the Files tab on bottom portion of uTorrent. Right-click the problematic file and select Don't Download.

Some hard-to-finish downloads are simply the result of not enough seeds or peers. In this case, your only options are to wait in hopes that a seeder will sign on, or find a more popular torrent and start over. Your torrent could also be corrupt, in which case you'll also need to find an alternative source.

Is that uTorrent in Your Pocket, or Are You...Oh, it is uTorrent!

There's an easy way to add uTorrent to your repertoire of portable apps so you can lug the client around on your USB key or any number of portable devices (like your iPod). The first thing you need to do is download the latest client (here) and copy it to your USB thumb drive or other storage device.

Next, create a new notepad file and save it as settings.dat. If you're unable to change the file extension from .txt to .dat, open up My Computer, press ALT+T, and select Folder Options. Click the View tab and uncheck 'Hide empty drives in the Computer folder.' Copy the settings.dat file over to the same directory on your USB drive as uTorrent and you're good to go!

Open Up Access Through Your Router and Firewall

Don't despair if you can't seem to connect to any seeders or peers, or if your downloads always trudge along at a snail's pace even when there are a ton of seeders. You probably just need to configure port forwarding for your uTorrent client, or whatever BitTorrent client you're using.

In a nutshell, port forwarding is a way for your router to forward IP addresses from an external location -- in this case, seeders and peers -- to an internal address, which is your PC. To find out which port uTorrent is trying to use, click on Options>Preferences>Connection. Make sure that both the 'Enable UPnP port mapping' and 'Enable NAT-PMP port mapping' checkboxes are marked. While you're in there, you can also check 'Add Windows firewall exception,' or we can do this manually later. Take note of the number next to the 'Random Port' button.

Now that you know the port number, it's time to configure your router. Access your router's administrative controls by firing up your Web browser and typing 192.167.1.1 into the address bar and hit enter.You'll be prompted for your username and password, which will vary depending on your router make and model. Try typing admin in both fields, or leaving the password field blank. If that doesn't work, you'll need to consult your router's manual or online support site for specific instructions.

You should now be in your router's control panel. We're using the customized Tomato firmware for our Linksys router, so yours will probably look different than our screen grab above. If you're using a Linksys router, click on Applications & Gaming>Port Range Forward (once again, if you're using a different router, consult your documentation on how to find the port forwarding section). Choose a blank row and type uTorrent in the Application field. Type the port number number you recorded earlier in both the Start and End fields. Change the protocol to Both (TCP and UDP), and be sure to check the Enable box. Save and exit.

Slow or non-existent connections could also mean your firewall is blocking access. To manually create an exception for uTorrent, click on the Start menu and type in Firewall. Click on Action and select New Rule, which will bring up the New Rule Wizard. Select Program as the Rule Type and hit Next, then click the Browse button to find and enter the path to your uTorrent client (C:\Program Files (x86)\uTorrent \uTorrent.exe by default). Keep the default settings as you click through the Wizard.

Set Bandwidth Limits and Maintain a Reasonable Ratio

Left unchecked, uTorrent and every other BitTorrent client will consume all the bandwidth it can and bog down your Internet connection in the process. That's okay if you're heading off to bed, but during the day, you'll feel as though you traveled back in time to the days of dial-up.To prevent this happening, we need to set bandwidth limits.

Select Preferences from the Options menu, or press CTRL+P, and then click on Bandwidth. Everything is laid out pretty logically, so it's just a matter of filling in the blanks. Uploads and downloads are measured in kilobytes per second (kB/s), and if you want to leave these at unlimited, choose 0. Otherwise, set limits that work for your Internet connection.

To help take into account overhead, we recommend measuring your real-world broadband speed at SpeedTest.net. Use your SpeedTest results to help determine how much bandwidth you want to fork over to BitTorrent.

You may be tempted to allocate very little upload bandwidth to BitTorrent, but this isn't necessarily a good idea. Remember how your mother always told you it's better to give than it is to receive? The same concept applies to BitTorrent, at least in part. The whole concept of BitTorrent is built around the idea that everyone shares and you should strive to upload as much as you download.

Rather than constantly keep an eye on your share ratio, you can configure uTorrent to automatically adjust the amount of bandwidth to allocate to a file once a set ratio has been met. To do this, go back into Preferences and click on Queuing. In the Seed While section, set whatever ratio you're comfortable with. Check the 'Limit the upload rate to' box and choose 0 if you want to stop seeding once you've reached your goal.

Use RSS Feeds with BitTorrent

Several BT clients now come with integrated RSS support. That's great news, because BitTorrent and RSS makes keeping up with your favorite TV shows or Podcasts super easy. Once again, we're going to assume you're using uTorrent.

First, you need to figure out which RSS feed(s) you want to subscribe to. There are a lot of resources out there, including ezRSS.it and LegalTorrents.com. Once you've picked out a (legal) feed, open up uTorrent and right-click the RSS icon next to All Feeds in the left-hand column. Select 'Add RSS Feed...' and enter in the feed's URL. Under Subscription, you can choose whether or not to automatically download all items published in the feed. We're going to leave this unchecked.

Depending on the feed you subscribed to, you may have signed up to much more than you bargained for. We're not interested in all of these, and luckily, there's a way to fix this and cut back the cruft. Right-click an episode you are interested in watching and select Add to Favorites.

Click on Options>RSS Downloader, or press CTRL+R. Under the Favorites tab, click on your RSS feed. This brings up the RSS Downloader window. Click on the RSS feed under the Favorites tab. In the Quality drop-down menu, select whichever formats you're interested in, keeping in mind that you can choose more than one. Click the Smart ep. filter checkbox to make sure you don't end up downloading duplicate copies, and if applicable, check the Episode Number box to define which seasons and episodes you're interested in.

Any new episodes in your feed should now start downloading automatically.

Circumvent ISP Throttling with SSH

Do you suspect your ISP is putting the brakes on Bittorrent traffic? You can avoid this practice by making an end-run around your ISP and connecting with a Secure Shell (SSH) connection. Be warned that this most likely isn't a permanent solution, which we'll get to in a just a moment.

You're going to need an SSH account to start things off, and that's going to be the trickiest part. There are a lot of free shell providers out there, but most of them place strict restrictions on what you can do with them. You're going to have to do some digging to find one that won't frown on tunneling BitTorrent traffic, they may require a donation, and you could end up waiting several days for your account to be approved. You can start your search here.

Once you have an SSH account, download and install Putty, and then run the app. Make sure the SSH radio button is selected. Type in your SSH account information (Host name or IP addy and port).

Next, expand the Connection tree and select SSH>Tunnels. Enter in any available port number. Mash the Open button and enter in the username and password given to your by your SSH provider.

Open up uTorrent and navigate to Options>Preferences>Connection. Under Proxy Server, select Socks4 from the pull-down menu. Type localhost in the Proxy field and enter in your port number from above. Click Apply and then restart uTorrent.

Transfer Torrents to another Location

Maybe you're running out of space on your hard drive, or perhaps you're wanting to do some spring cleaning and organize your data. Whatever the reason might be, transferring your torrents from one spot to another is pretty quick and painless, once you know how.

Stop any downloads that are in progress by right-clicking and selecting Stop, or hitting the big red Stop button in uTorrent's menu bar. Next, right-click the torrent(s) and select Advanced>Set Download Location... Navigate to the new download spot and click Save, but don't change the file name.

See how easy that was? All that's left is to highlight the torrent(s) and mash the green Play button. uTorrent will check the files to see how much is left to be downloaded, so just be patient whie it does its thing.

Transfer Torrents to uTorrent

So you decided to take our advice and ditch your current BT client for uTorrent. The only problem is, you've already invested a ton of time into downloading a bunch of large Linux distros, and the last thing you want to do is start from scratch. You're in luck, because you can have your cake and eat it too (what else would you do with it?).

In this example, we're going to show you how to migrate one or more partial BT downloads from Vuze (formerly Azureus) to uTorrent. The first thing you need to do is figure out where Vuze is storing the downloaded data. By default, this will be C:\Users\USERNAME\Documents \Azureus Downloads. If that directory doesn't exist, go to Tools>Options>Files to find out where Vuze is hiding your data.

Stop any downloads that are currently in progress and close out Vuze. Open up uTorrent and select Options>Preferences>Directories and follow these steps:

Check the 'Put new downloads in' checkbox and create or select a folder to store downloads in progress (we created a directed called 'Downloads' on our Desktop).
Check the 'Move completed downloads to' checkbox and create or select a folder to store your finished downloads (we created a folder called 'Completed' inside the Downloads folder).
Check the 'Automatically load .torrents from' checkbox and create or select a folder to store your torrent files (we created a folder called 'Autoload' on our Desktop).
Click Apply and close out uTorrent.

Next, navigate to C:\Users\USERNAME\Documents\Azureus Downloads or wherever it is Vuze was storing your partial downloads. Move (don't copy) the data to the directory you specified in Step 1 above. Note that some clients, including Vuze, will sometimes add an extension to unfinished downloads. If that's the case, you'll need to remove it or else it could trip up uTorrent.

If you still have the original .torrent file that was used to initiate the download, move it (don't copy) to the Autoload folder you created in Step 3 above. If you don't have it, you'll need tor re- download the original .torrent and put it in the Autoload folder. Once the .torrent file is in place, fire up uTorrent, and after a few seconds, your download(s) will initialize and pick up where they left off in Vuze.

Setup an Automated Throttling Schedule

We're not too keen on having our ISP choke our BitTorrent bandwidth, but that doesn't mean we're entirely opposed to throttling. We just want it to occur on our own terms, not someone else's. Fortunately for us, uTorrent's built-in Scheduler makes this super easy. With the Scheduler, we can configure uTorrent to automatically kick on at night when we're fast asleep. That way, we'll have all the bandwidth we need during the day, and still wake up to a finished download in the morning.

To set up a schedule, go to Options>Preferences>Scheduler. Click the 'Enable Scheduler' checkbox, which will light up the grid in green. There's a handy legend right below the grid that tells you what the colors mean, but to reiterate, dark green boxes tell uTorrent to download and upload at full speed, light green boxes tell uTorrent to only use a set amount of bandwidth (which you can configure), the white box is used to indicate when you want uTorrent to remain idle, and the light gray box tells uTorrent to seed (upload) only.

Because we work during the day and do a ton of Web surfing to research awesome stories and features for our homepage, we want to uTorrent to go into a state of comatose during working hours. We also like to unwind and frag our friends after a full day of work, and that can sometimes last until late at night. So to play it safe, we're giving uTorrent the green light (literally) to do its thing from 1AM until 8AM, but not during any other hours.

As you highlight a square, it will tell you what 1-hour time slot it is for. To save time, you can click and drag multiple squares rather than clicking each one individually. Once you're finished, you should have something that resembles the above.

Add One-Click BitTorrent Downloads to Firefox's Reportoire

Don't feel like fussing with BitTorrent clients every time you want to download a BT file? You don't have to! One of the coolest extensions for Firefox is FireTorrent.

With FireTorrent installed, just click on a .torrent file and Firefox will download the related data files just like a normal download and even show you the progress in the Download Manger. And if you'd rather let a third-party handle a particular .torrent, just right-click and select Save Link As.

FireTorrent isn't nearly as robust as most third-party BT clients, but you are afforded some basic options, including which port to use, download and upload bandwidth allocation, the ability to encrypt BT connections, and a few other light-weight customizations. It's barebones, but it gets the job done!

Update uTorrent Remotely with a Single Click

The BitTorrent WebUI add-on for Firefox combines the one-click sex appeal of FireTorrent with the WebUI capabilities we set up earlier. Once configured, all you need to do is click on a torrent and this add-on will update your BT client at a remote location, provided you're using either uTorrent or Vuze.

Follow our instructions earlier on how to setup uTorrent with WebUI. Next, install the BitTorrent WebUI add-on available here and configure it with the same settings you used to setup uTorrent's WebUI.

Now all you need to do is find some torrents and start clicking!

Block Malicious IPs

Tinfoil hats tend to chaffe our head and freak out our co-workers, which are pretty big trade-offs for a little bit of peace of mind. But there's a better way to protect our privacy from prying IPs. PeerGuardian 2 is an IP blocker for Windows that integrates support for mulitple lists, automatic updates, and blocks a bunch of protocols. It keeps a constantly updated list of blacklisted IPs known to track your P2P activity.

If you're a real conspiracy theorist, PG 2 gives you plenty of options to keep the establishment from building a database about your online activity. Checking the P2P box should be enough for most users, but if you're convinced you're the center of the BT universe, go ahead and mash your mouse button on every checkbox.

You can also configure an update schedule for PG 2 to make sure you're always one step ahead of the man. And for more than you ever wanted to know about this program, reference the extensive Wiki here.

Supercharge Windows XP for Faster Uploads

If you decided to stick with XP for a little while longer, you're not just missing out on what Windows 7 has to offer, but you could be hamstringing your download speeds. That's because Windows XP limits the number of TCP connections to no more than 10, which could prevent you from hooking up with a larger number of peers. So should you upgrade to Windows 7? Yes, but not because of the TCP limit.

A German programmer developed a nifty little patch that removes the 10 TCP limitation so you can set it at whatever number you want. Download the patch here, then fire up uTorrent and navigate to Options>Preferences>Advanced and look for net.max_halfopen.

Trick Out uTorrent with Skins

For all of its functionality, uTorrent isn't much to look. And maybe that's right up your alley, but if not, there's a wealth of skins to experiment with until you find one that look that's just right. And you can skin different parts of uTorrent individually, inculding toolbars, status icons, tab icons, and program icons.

Download your skin(s) from here and place them in C:\Users\[USERNAME]\AppData\Roaming\uTorrent. Restart uTorrent and enjoy your new look!

20 Essential Tweaks and Tips Every Firefox User Should Know

Norman Chan — Tue, 10 Nov 2009 11:00:00 -0600

Firefox may be your default browser, but that doesn’t mean you really use it to its full potential. Mozilla’s browser is a big threat to Microsoft not because it’s fast and full of unique features, but because it’s also extremely customizable. Add-ons, style scripts, and hidden preferences let you personalize your Firefox experience to meet your tastes and needs. Sure, you may know about hidden easter eggs like the about:robots page, but we’re going show you the 20 most essential tips, tricks, and tweaks to this super browser.

Undo Closed Tabs and Windows

This is actually a feature that has been around since before Firefox 3, but we’re often surprised by how many people don’t know about it. Firefox stores a record of every open and closed tab in all windows for each browsing session. So if you accidentally closed a tab, you can bring it back by pressing Ctrl + Shift + T. The restored tab retains its surfing history as well, and you can bring back old tabs even after you’ve opened several new ones since the initial close.

Speed Up Browsing

Firefox 3.5 is fast at loading pages, but its operational speed can get bogged down by overloading extensions. But you can add further optimizations to the browser by making a few tweaks behind the scenes. Load up the about:config page (by typing about:config in the location bar), and make the following changes:

Set network.http.max-connections to 96 – This sets the total number of HTTP connections Firefox can make to a web server. The default value is 30 (raised for the previous default of 24), but if you have ample bandwidth, increase the number speed up the loading of multiple-tab bookmarks.

Set network.http.max-connections-per-server to 32 – The default is 15, but you can raise it to increase the number of connections made to a single server. This is useful if you’re planning on browsing a site while downloading many files from it at the same time.

Set network.http.max-persistent-connections-per-server to 8 – Raising this setting from 6 to 8 improve performance when working through multiple pages of a site. We don’t recommend setting this value to anything higher than 8.

Set network.http.pipelining to true – Pipelining is an application of the HTTP 1.1 protocol where multiple requests can be sent to a web server before any responses are received. Not all servers support it, but this will improve your browsing speed if you’re on a high-latency (slow) connection.

Set network.http.proxy.pipelining to true – Same as the setting above, but only applies if you’re using a proxy connection.

Set network.http.pipelining.ssl to true – If you’re encountering problems with pipelining enabled, the root of the problem may be a broken proxy server sitting between you and the target server. SSL (secure) sites don’t have this problem, so this setting will let you turn on pipelining for those sites only, regardless of the other pipelining settings.

Set network.http.pipelining.maxrequests to 8 – With pipelining enabled, this preference specifies the maximum number of requests to make to a server at once. Raising the default value from 4 to 8 will speed up your requests to a server, but will cause a small delay if one of the requests fail.

Use Gmail as Your Default Mail Application

When Firefox 3 was first released, one of the new features was the option to associate html protocols with web applications, such as launching a webmail service when clicking a “mailto:” link. Unfortunately, at the time of launch, only Yahoo’s mail client was officially supported, and users had to either use extensions or manipulate some javascript code to enable Gmail as the primary mail handler. The current iteration of Firefox has included Gmail in the web app client list, and here’s how you turn it on.

Go to Tools-> Options, and select the Applications tab. This is a list of protocol and content associations, with their respective plug-ins for each type of content (ie. Mp4 video). In the search field, type “mailto”. Then, in the Actions drop down menu, select Gmail as your default client. That’s it! The next time you click on an email link, Firefox will open up Gmail in a new tab to send an email. Bonus tip: download and install the Better Gmail 2 add-on to add extra UI features if you’re planning on using Gmail as your primary mail client.

Disable the Awesome Bar

We think that the Awesome Bar lives up to its name – its auto-complete feature lets us get to our favorite websites even if we don’t remember the exact URL. But not everyone wants Firefox to auto-complete location bar text, especially if you visit sketchy or embarrassing sites that share common URL characters (ebay and piratebay, for example). You can disable the Awesome bar by turning off the XUL richlistbox widget that powers it.

First, open up the about:config page. Type browser.urlbar.matchBehavior in the Filter field, and right click the sole resulting entry. Click Modify, and change the value of the setting from 1 to 2. Now, whenever you start typing a URL in the location bar, you only get suggestions from websites that start with that text, not just any with those string of characters.

Now, if you want to make the Awesome Bar to not show any suggestions for pages that you have visited or bookmarked, and only show suggestions for URLS that you have manually typed, go to the browser.urlbar.default.behavior preference in about:config and change its value from 0 to 49.

3 Quick Location Bar Style Fixes

Always show the GO button

By default, the GO button the far right of the location bar only shows up if the bar is empty or if you’ve typed in something new. To make the button stay visible, go to your user Profile directory (C:\Documents and Settings\USERNAME\Application Data\Mozilla\Firefox\Profiles\ in Windows XP), navigate to the Chrome subdirectory, and create a new blank file called userChrome.css. This file lets you make stylesheet changes to Firefox. Open up the file with Notepad and type the following at the end of the file:

#go-button { visibility: visible !important; }

Restart Firefox to put this change into effect.

Disable the RSS Feed Button

If you’re not a fan of web feeds, you have no need for the RSS button at the end of the location bar. Disable it by opening up the Chrome.css file you created before in your Profile directory, and add the following line:

#feed-button[feeds] { display: none !important; }

Restart Firefox to put this change into effect.

Use Small Location Bar Icons

The location bar itself isn’t terribly tall, but every pixel counts when you’re using a tiny screen netbook or have stacked additional toolbars like the Booksmarks bar or a StumbleUpon bar. Shrink the Location Bar by right clicking the any toolbar and clicking the “customize” option. At the bottom of this screen, check “Use Small Icons.”

Reasonably Cut Ram Usage

Firefox is generally good about memory management, so we don’t normally recommend memory allocation tweaks because of the performance tradeoff. But there is one setting in Firefox that may be useful if you tend to have many browser windows and tabs open but minimized at the same time.

Open up the about:config page, and right click anywhere in the window. Select New->Boolean to create a new preference setting, and type “config.trim_on_minimize” in the pop up box. Next, choose True as the default value. This preference will offload memory using from RAM to virtual memory on your hard drives when windows are minimized. The only caveat is that “waking up” this minimized window will take a little longer than usual, since Firefox will need to transfer its state back to physical memory.

Additionally, we recommend that you try the RAMBack add-on, which gives you notifications when and how much memory can be freed up from RAM.

Browse Privately on a Public Computer

A feature actually first introduced in IE 8, Firefox’s private browsing mode lets you surf the web without retaining any URL history, form and search fields, passwords, cookies, or web cache on the local machine. This is particularly useful for surfing at work or on a friend’s computer, when you don’t want them to snoop around your shameful habits. Turning on private browsing is as simple: just hit Ctrl + Shift + P. Firefox will save your existing windows and open a new session (unfortunately, you can’t have both private and non-private mode windows open at the same time). In the privacy options settings, you can even set Firefox to start in private browsing mode by default.

Customize the New Tab Page

One thing that Chrome and IE 8 do better than Firefox is the new tab page. When you open a new tab in Firefox, it defaults to about:blank, which, appropriately, is a blank page. Mozilla actually acknowledges this shortcoming, and has been experimenting with various new types of new-tab landing pages in their Mozilla Labs department. The latest prototype shows you a page with Frequently Visited Sites, and a “You Might Want to” suggestion based on what’s in your clipboard.
You can download and install it here.

6 Essential about:config Tweaks

About:config is amazingly powerful – it lets you change almost every aspect of how Firefox functions. Going through and explaining what every preference does would not only be an impossible task, but also unnecessary since most people are happy with the default settings. There are, however, a few settings that we think are essential to change. Make these tweaks first when you encounter a fresh install of Firefox.

browser.urlbar.autoFill = True
Enable auto-complete for URLs when typing into the location bar.

browser.sessionstore.max_tabs_undo = 15
Increase the number of closed tabs that firefox has stored in its cache to 15.

browser.tabs.tabMinWidth = 75
Show more tabs in a single window by narrowing the minimum width of a tab.

browser.search.openintab = True
Automatically open new search results in a new tab

middlemouse.paste = True
Use the middle mouse button to paste text from your clipboard.

browser.blink_allowed = False
Disables annoying text with the Blink tag.

Make Smart Bookmarks

A really sweet feature in Firefox 3 is the ability to program your own smart bookmarks. These are dynamic bookmark groups that change depending on your browsing history. For example, you can have it set to show the 10 most popular pages you’ve visited within a certain domain, or the 15 most popular sites you’ve visited that contain a specific keyword in its title.

Open up your Organize Bookmarks window by typing Ctrl + Shift + B. Choose the folder you want to create your new smart bookmark, and create a new bookmark with the Organize menu. In the location bar, enter a string using the following syntax:

place:queryType=A&sort=B&maxResults=C&domain=D&terms=E

Replace A, B, C, D, and E with whatever you choose, based on these rules:

Querytype= 0 to only search your history, 1 to only search your bookmarks, 2 to search both

Sort = 1 for A to Z, 2 for Z to A, 3 to sort by most recently visited, and 8 to soft by most often visited

Domain = the domain you want to show results for, such as “maximumpc.com”

Terms = the word or words you want to show results for.

For more syntax options and explanations, visit Mozilla’s reference page.

Back Up Your Bookmarks

Keep your bookmarks backed up and synchronized across multiple computers using the popular Xmarks add-on. Formerly known as Foxmarks, this extension securely stores your bookmarks (and even passwords) on their servers, and can even analyze your saved links to give website and tagging suggestions. It’ll even sync across multiple browsers, in case you use both Firefox and IE (Chrome support eventually coming).

Know the Location of Your Profile and Settings

What if you accidentally delete your bookmarks or profile settings before storing them in the cloud? Not to worry – Firefox makes periodic backups of your bookmarks, safely backing them up in a hidden folder. You can find and retrieve them in Windows easily. First, open up Windows explorer, go to folder options, and enable viewing hidden files. If you’re using Windows XP, your Firefox profile backups will be located in the following directory:

C:\Documents and Settings\USERNAME\Application Data\Mozilla\Firefox\Profiles\

Just replace USERNAME with your Windows user account name, and sort the .json files by date. Copy and save the desired backup file to your Desktop, open up Firefox, and choose the Import and Backup option under the Bookmarks menu. Locate the .json file on your Desktop, and open it to restore your bookmarks.

In Windows Vista and 7, the backups are stored in:

C:\Users\USERNAME\Application Data\Roaming\Mozilla\Firefox\Profiles

4 Scroll Wheel Secrets

Open a link in a new tab by hovering over it and clicking the middle mouse button.
Close a tab by hovering over the top of the tab and clicking the middle mouse button.
Hold Shift and scroll your mouse wheel to move forward or backward through your history.
Enlarge or shrink the size of text on a page by holding Ctrl and scrolling up or down.

Advanced Spell Checking

Firefox’s built-in spell checker is useful for using web content management systems like Wordpress for blog entries or Google docs, but the default setting only spellchecks fields that are bigger than one line. Enable single-line spellcheking (like for Google searches) by changing the following preference in about:config: layout.spellcheckDefault = 2

Additionally, you can add different language dictionaries to the spell-check database by picking and installing the right packages from Mozilla’s language packs page. Right click any multi-line text field and you can choose to alternate between different languages for spell checking.

And in case you’ve ever unintentionally added a word to the Dictionary, you can remove the entry by opening the persdict.dat file stored in your user Profile directory. Using a text editor like notepad, delete the line containing your unwanted word, and save the file.

14 Essential Keyboard Shortcuts

Ctrl+T – Open a new tab
Ctrl + Tab – Next tab
Ctrl + 1-9 – Jump to a specific tab
Ctrl+W -- Close the current tab
Ctrl+N – Open a new window
Alt+Home – Go to your home page
Ctrl + R – Refresh the current page. F5 also works
Ctrl + Shift + R – Refresh the current page after flushing its current cache
Ctrl+F – Find specific text in the current page. You can also use /
Ctrl+D – Bookmark the current page
Spacebar – Scroll a page down
Shift+Spacebar – Scroll a page up
Ctrl+K – Put the cursor in the search field
Ctrl+L – Put the cursor in the location bar

Make Websites Work and Look the Way You Want

Browse websites the way you want. Use the Greasemonkey add-on with user-created scripts to automate and customize the way the way websites behave and look. You can make MP3 file links play with an in-line MP3 player, or make Google display Twitter search results at the top of all search pages. There are thousands of Greasemonkey scripts that you can use, and they’re all free to download.

Stylish lets you easily employ themes (called Styles) for any website without having to mess with CSS code. Like Greasemonkey, there is a sizeable database of preconfigured styles that users have created for you to try.

Disguise Firefox as Internet Explorer or an iPhone

Even if you don’t want to run Internet Explorer, there are some web services that only work if you use Microsoft’s browser (such as web outlook or Windows Update). IE Tab gives you the option to render pages using Internet Explorer or open new tabs using the IE engine. You can make specific sites always open with IE Tab as well.

User Agent Switcher is an add-on that doesn’t change the rendering engine, but allows you to make Firefox pretend to be a different browser when it retrieves information from a server. For example, you can have Firefox pose as an iPhone to view mobile-specific pages.

Make use of the Favicon

The favicon -- a website’s shortcut icon – is pretty to look at, but for the most part is pretty useless. Firefox lets you click the favicon next to a site’s URL in the location bar to display identity information, but most sites don’t utilize this feature. However, you can use the favicon as a quick way to access and manage stored cookies for specific websites. Just hit the “more information” button after clicking a favicon to open up that site’s page information window. Here, you can view and delete individual cookies for just this site, and even access saved passwords stored for users. It’s a really sneaky way to steal someone’s email password if you’re using their computer.

Manage Auto-Complete Suggestions

Forget to turn on private browsing mode and leave an embarrassing site in your URL history? You can delete individual auto-complete suggestions by hovering your mouse over the suspect URL and pressing the Delete key (not backspace) on your keyboard. The same trick also works for stored search history in your search bar, or any other auto-complete forms like user login.

Download like a Pro

From our power downloading guide: The Alpha and the Omega of downloading extensions, DownThemAll! is as simple to use as its name implies. When you activate this add-on for a page you're surfing, DownThemAll gives you a list of every potential downloadable item on the page--everything from ZIP archives to JPEG images. You can grab the entire page's contents and dump them in a folder, or you can selectively filter for only the file extensions that you're actually interested in. Never before has pilfering the entire contents of a Web site been quite so easy.

How-To: Turn Your Windows 7 PC into a Wireless Access Point

Mark Edward Soper — Mon, 02 Nov 2009 11:00:00 -0600

If you've ever been in a situation when you absolutely, positively, need to share a network connection wirelessly, and you have a PC with a wireless adapter that runs Windows 7, Connectify (from wireless mesh networking company Nomadio, Inc.) is the answer. Connectify (currently in beta) turns almost any Windows 7 PC with a working wireless network adapter into a fast and secure wireless access point.

What You Need

A PC running Windows 7*
A working wireless adapter**
Software from the Connectify Me website
About 15 minutes of your time

*Connectify works with Windows 7 final and Windows 7 RC

**Update - some Intel network adapters might not work with Connectify - see Paul Lilly's comment below

Getting Started

Navigate to the Connectify Me website and click either the Download Beta button or Beta Test Now shield.
Enter registration information and click Submit.
Click the Click Here to Download Connectify link to download it immediately (instead of waiting for the promised email link which you might, or might not, receive on a timely basis).
Run the 1.41MB installer, and provide UAC information if prompted.
After you sign off on the license agreement, the installer does its work.
Click Next to continue, and click Finish. By default, Connectify will start, and a readme will open in your browser.

Setting Up Connectify

If you don't see the Connectify icon in the notification area, click the up arrow pointer to display additional icons. Click the Connectify icon.

The first time you start Connectify, you will see an error message. That's because Connectify needs you to provide a passphrase. Click the passphrase field and enter the text you want to use. You must enter at least eight characters (up to 32) for your passphrase text (you can display or hide the text as desired). Connectify uses WPA2 AES encryption for maximum security.

By default, Connectify uses Connectify as its SSID. To change the SSID, enter the name you prefer in the WiFi Name field.

If you have more than one connection you can share, select the connection to share from the Internet pull-down menu. You can use Connectify to share a wired connection (which is what I used for this article), or a wireless connection. You need only one wireless adapter to make sharing work, even if you're sharing a wireless connection wirelessly.

Click the Hotspot Off button to turn on the Connectify access point.

Connecting to a Connectify Access Point

Whether you use Windows XP, Windows Vista, Windows 7, MacOS, or Linux, connecting to the Connectify software access point uses the same procedures you use to connect to any secure wireless access point that broadcasts its SSID:

Select the SSID used by the network
Enter the passphrase when prompted
Make the connection
Make any firewall or other configuration changes requested by your wireless network client

Once other PCs have connected to the Connectify software access point, Connectify lists the computer(s) connected to it by their network names and IP addresses.

When you shut down the connection, Connectify "remembers" who was connected to the network, listing them as "disconnected clients."

Conclusion

Connectify works - and works well - because it relies upon new networking features built into Windows 7. Right now, Connectify costs nothing to try – and it provides a solid, secure, and fast connection. Whether you're looking for a quick way to share a wired connection in a hotel room or conference center, add wireless capability with Internet access to a home or office wired network, or set up a quick, easy LAN party without fiddling around with your normal network configuration settings, Connectify looks like a winner. It's one of the coolest reasons to move up to Windows 7.

How To: Properly Clean Your PC

Florence Ion — Thu, 29 Oct 2009 11:00:00 -0500

Every computer collects dust over time. When the computer is running, it creates a field of static electricity, which in turn attracts clumps of dust and hair. These cluttering particles can easily collect around your processor, power supply, and case fans, and can block airflow and lead to overheating. This is why an important part of taking care of a computer is making sure that it’s clean.

To that end, we’ve put together a comprehensive guide on how to clean your computer hardware and peripherals to make your rig look as good as new. We took a 4-year-old computer and thoroughly cleaned it using a few household supplies. All it took was a little bit of patience and a few hours and we managed to get some impressive results. Follow along below to achieve the same cleanliness Zen with your own machine.

And once you're done, read our guide to giving your PC a professional wiring job!

What you need:

Compressed air
Isopropyl rubbing alcohol
Lint-free or microfiber cloths
Paper towels
Q-tips
Scissors
Swiffer Dry Refill sheet
Masking tape
Vacuum with a removable handle and crevice tool

1. Start with Cord Management

First, let’s start with the external cables. Begin by untangling any that have become entwined. Now, grab a soft, microfiber cloth and dampen it with a bit of isopropyl rubbing alcohol, then run it along the length of all of your cords to remove any dust that may have built up (image A). Then, grab a few zip ties and begin organizing your cables in terms of their location in your machine: For example, the wires connecting peripherals reside toward the top; the DVI connector and power supply cord are toward the bottom, and so on. This will prevent your cables from getting tangled over time. Don’t group any power cables with speaker wire. Make sure to put on the zip ties toward the middle of the cords to give yourself some flexibility when you disconnect or connect devices (image B). Now, unplug your cable bundles so they’re out of the way while we clean the inside of your machine.

(Image A)

(Image B)

2. Cleaning Your Case

Now, make sure the power supply is turned off, lay your case on its side, and remove the side door. First, you want to inspect the internal data and power cables to make sure they’re all connected and well-fastened (image A). If there are any damaged cables, consider replacing them entirely—do not attempt to fix them with electrical tape. Generally, electrical tape is only used for insulation purposes, not to patch-up wires, and this rule is especially crucial when dealing with the inside of a computer.

(Image A)

Next, you want to get rid of the dust bunnies around your motherboard. Grab a can of compressed air and make sure that the straw is securely inserted. Stand the case upright—when you shoot at it, make sure the can of compressed air stays upright as well (image B). Do not tilt the can on its side or shoot at the computer sideways.

(Image B)

Squeeze the trigger to blast air in the direction of the key components in your case: the crevices in between your fans, the drive bays, connection ports, and any other areas that are plagued by dust and tiny hairs. If you find that you have excess grime or stray dust balls rolling around, you can actually use your vacuum cleaner to deal with them, provided that it’s equipped with a removable handle and a crevice tool. Vacuum away from the motherboard and use it only to eliminate giant dust bunnies that fall to the bottom of the case. Additionally, if you have an air filter in your case, remove it and run it under warm water to remove the dust. Be certain it’s completely dry before re-inserting.

3. Wipe Down Fans

With a different piece of lint-free cloth, wipe down your fan blades, then sprinkle the cloth with a few droplets of 90 or 99 percent rubbing alcohol solution and run it along the inside of your case (image A). Use a Q-tip to clean tight spots like your CPU cooler’s fan blades (image B). When you’re finished and everything has dried, feel free to close up the case.

(Image A)

(Image B)

4. Make Your Own Filter

A great way to keep dust from infiltrating your PC is to create your own air filter using a Swiffer Dry Refill sheet. All you need to do is cut the sheet to fit the grill on the outside frame of your case and affix it with a few pieces of masking tape. In this instance, we pasted it between the outside of the case chassis and the front-frame. Be sure to place this filter only where air is being sucked in and remember to replace it every few months (or as it visibly accumulates dust).

5. Clean Your Mouse

Assuming your cords are still unplugged, dampen a lint-free cloth with rubbing alcohol and clean the outside shell of the mouse, paying attention to any residue on the buttons. It’s important that you exercise caution while cleaning peripherals like an optical mouse—cleaning solutions should never come in contact with the optical sensor at the bottom of the mouse—it could ruin it. Also, avoid using paper towels; stick to lint-free materials so that you don’t risk leaving behind any fluff that could stick to the sensor.

6. Clean Your Keyboard

One easy way to clean gunk out of your keyboard is to turn it upside down over a sink and smack the bottom to knock out the colony of crumbs that have undoubtedly settled in. Run through the keyboard’s spaces with a can of compressed air to get loose crumbs and hairs out of the way, and then use rubbing alcohol and Q-tips to clean grease off the surfaces and in between each key.

For a more thorough wipe-down, you could even stick your keyboard in the dishwasher, though we warn you that this is NOT a solution for expensive keyboards with LCD displays and USB slots—there is also a very real chance that it will destroy your keyboard. Before placing it inside the machine, bundle the cord and put a plastic bag over it, making sure it covers the USB/PS2 plug and that it is securely sealed with a rubber band.

Situate the keyboard on the top rack of the dishwasher so that it is facing down—we want the jets to hit up against the keys and wash off the residue. If your dishwasher has a speed dry cycle, turn it off—if you let the inside get too warm it could warp the plastic or crack the circuit board from thermal expansion. For the first run, we suggest omitting soap altogether, but to remove tougher stains, a pea-size amount of soap is also OK, but use at your own risk. After running it through a light cycle, let the keyboard dry for several days or until all the water has dried before reconnecting it.

7. Clean Your Monitor

Grab a microfiber cloth and gently wipe your screen to free it of dust, fingerprints, and any other smudges. You can make your own screen cleaning solution using a half-and-half mix of 70 percent isopropyl alcohol and distilled water, or you can pick up a premixed solution from any computer store or office supply retailer. Under no circumstances should you use Windex or paper towels to clean an LCD screens, especially those with anti-glare surfaces. If you’re using a CRT, use a few dabs of rubbing alcohol to gently wipe away greasy spots from the screen.

Next: Give your PC a professional wiring job!

Have any PC cleaning tips or dusty PC horror stories? Share in the comments section below!

How-To: Configure and Schedule Automated Backups in Linux

Will Kraft — Wed, 14 Oct 2009 15:00:00 -0500

Regardless of the operating system you are using, data loss is inevitable. Sooner or later, it will happen to you—the only question is how much data you will lose. Although RAID can act as an insurance policy for hardware failures, it was never designed to serve as a backup and will not perform this task well at all. Human error is always the greatest concern since important files can be accidentally overwritten or deleted at careless moments. It is easy to fall behind on your backups or get complacent; without recent backups you have no recovery strategy. This guide will help you automate your backups on your Linux rig so you will always have your files up to date.

Step 1: Get the Requisite Tools

Before you can backup your data, you need an acceptable storage location to copy it to. Optical media like CD-R/RW or DVD-R/RW discs were once a popular (but not necessarily the best) medium to back up to since they held a lot of data for the time and were fairly cheap. Cheap optical media is suitable for short-term storage, but should not be relied upon for the long-term because of the possibility of scratches, oxidation, or organic dye breakdown. (CD rot) Optical media is now even less practical than it used to be since most personal data greatly exceeds what most disc formats can hold. It would take many discs (or one or more discs in a still-expensive format like Blu-ray) to conduct a single backup session. It used to be common practice to include multiple redundant copies of a file on a disc or spread across several discs to improve the chances of recovery in case of damage, and this would inflate the disc count even more. Ultimately, it just isn't worth using optical discs for backup anymore.

Today, the only practical means for backup is either an external hard drive (or several of them, if you want maximum protection) or an external server. It is best to rely on a combination of these methods instead of just one to increase redundancy. In any case, the hard drive(s) should be large enough to accommodate both your current existing data in addition to any foreseeable growth. In the case of servers, you should definitely use a remote server if you have access to one (if you buy web hosting and have plenty of space left on your account, that would be ideal for backups) Regardless of the storage mechanisms you use, the actual file transfer operations should be done with a program called Rsync.

Step 2: Set Up Rsync

Rsync is a program that copies data from one location to another. Although another program, cp, exists for this purpose, Rsync is far more advanced and efficient; while cp can only copy entire files from one location to another on a local system, Rsync compares the source file to the destination file (if it exists) and only copies the newer parts of the source file to the destination. In this way, Rsync can synchronize data between two locations much like the Windows briefcase tool does. This saves an immense amount of time and bandwidth on backup procedures.

In addition to that, Rsync can sync files on both local and remote systems whereas cp can only work with local systems. (there is a remote version of cp called scp, but even it can only work with whole files) Rsync will be as slow as cp the first time you use it since the destination files must be copied in full to the new backup location, but subsequent sessions will be much faster. You should know that it may take anywhere from several hours to several days to complete the first Rsync session with a remote server, depending on the speed of your connection and the amount of bulk data you need to transfer. Furthermore, Rsync (via SSH) encrypts remote file transfer sessions to keep your data from being sniffed in transit.

Rsync is fairly straightforward. The basic syntax is as follows: “rsync -a [source dir] [destination dir]”. (the -a switch tells rsync to work in “archive” mode, which is ideal for backup functions) Although the basic command listed above will work once you specify the source and destination locations, there are many other options available to tweak Rsync. These can be discovered by reading the Rsync manual page (run “man rsync”).

Although the command line implementation of Rsync allows for easier automation, (more on that next) using Rsync in this way can be difficult for new users who are not used to the command line. In such cases there is a graphical frontend called Grsync that can vastly simplify the backup process. Grsync redefines the various switches as easy-to-understand checkboxes that can be set to the desired combination.

Grsync does have a degree of automation by allowing you to define and automatically run a session (grsync -e [session_name]) but standard Rsync is still much more versatile since you can specify commands directly instead of having to rely on predefined sessions.

Step 3: Cron

Once you have configured Rsync to backup your files, you are only halfway to having a viable backup plan. A decent backup solution must run regularly instead of intermittently, and all by itself Rsync will not update your files unless you manually invoke it. While you can remember to manually run Rsync every day, there is a far easier way to do it.

Linux and similar systems have a utility called Cron, which is essentially a scheduling tool for running other programs. Each user has a crontab file, which is a list of instructions for Cron to execute and the times each instruction should run. In this way, everyone (not just root) can use Cron. Cron works with the system clock; when the correct time for a planned event rolls around, Cron will automatically execute the command.

There are several ways to edit your crontab. The easiest way for new users to configure Cron is to use a frontend like gcrontab or kcron. More advanced users can edit the crontab manually in a text editor like Vim or Kate. To edit the crontab manually, open a terminal and type “crontab -e”. After that, you should check your system process list for a “cron” or “crond” process (root should own it) to make sure that the Cron daemon is running. After editing your crontab, you must restart the cron process ( run “sudo /etc/init.d/cron restart”) before your new changes will work.

Manual crontab editing looks daunting at first but is simple once you get the hang of it. Each row in the crontab list is treated as a separate command. Each row has several columns that must be specified: minute, (abbreviated “m”) hour, (abbreviated “h”) day of month, (abbreviated “dom”) month, (abbreviated “mon”) day of week, (abbreviated “dow”) and the command. Each column is delimited by a single space with no other marks, and it doesn't matter if each row lines up perfectly with the others or not. You can add times/dates as both real numbers (Cron uses a strange 24-hour clock, so noon is 12:00 and midnight is 00:00), abbreviated days of the week (Sun, Thu, etc.), and wild characters. (*) Anything defined with a wild character is interpreted by Cron as “all”, meaning that if the hour on a command is set to “*”, Cron will execute the command every hour. To configure something to run repeatedly at a certain interval, you can use a “split” wild character. (e.g. setting */2 in the hour field will cause the command to run once every two hours on the days you define.)

Cron is quite flexible; Ranges affecting everything between two values are defined by short dashes (-) while multiple nonconsecutive occasions are delimited by commas. For instance, if you wanted to run a command every day from the first of the month to the 10th, you would specify “1-10” in the “dom” field. Likewise, if you wanted a command to run every Monday, Wednesday, and Friday, you should declare “Mon,Wed,Fri” in the “dow” field.

Step 4: Put them Together

Now that you know about Rsync and Cron, you can probably already see how they can be used together to automate backup processes. Since decent backup procedure recommends backing up to multiple sources, you would have to create multiple crontabs each with a different rsync command. Fortunately, there is a far better way that can be handled with a single Cron job.

The various command shells on Linux (like Bash) have excellent support for scripting. Shell scripts are the Linux equivalent of Windows batch files and offer a way to quickly run multiple commands in a specific pre-defined order and with a preset configuration. If you have much experience at all on the command line, you should not find basic scripting very difficult (there are plenty of online guides to help you write scripts for bash and other shells if you run into trouble). Creating a shell script to hold the necessary Rsync commands is trivial; from that point, you can invoke the shell script in your crontab and each Rsync command will run at the appointed time you set in Cron just as though they were being invoked directly. It helps to specify the full pathname of the shell “/bin/bash $scriptname” in the crontab instead of the shortcut “./$scriptname” to make sure that Cron executes the job successfully. If you have sensitive data, you should definitely consider encrypting it before you place it on a shared server (like a web host). Encryption can be done with GPG in the shell script prior to transmission.

The only foreseeable problem with automated backup is that system configurations tend to change over time. Mount points and IP addresses can be reassigned without notice, and your script will not automatically update itself to include these changes. As long as your Rsync commands are out of date, your files will not be backed up properly and you will have no idea of the problem until it is too late. Therefore, it pays to manually run your backup commands often to check for problems and update your script as necessary.

Although Rsync can sync between locations on the local system without user input, it usually requires a password before it can sync to a remote system (it uses part of SSH's functionality for this). Since automated Cron jobs prevent user input, there is no way to provide the password when it is needed. Because of this, the default SSH behavior will not work for automated backups. You can get around this by setting up public/private key authentication for SSH; as long as the keys match, no password is required. Be forewarned that the automated key authentication will be broken if the IP address of the remote host changes (this is a deliberate feature to help prevent man-in-the-middle attacks) and that security is compromised slightly. Ultimately, it comes down to a trade-off between security and convenience, so choose wisely based on your situation and needs.