One of the most popular
uses for file synchronization software is the synchronization of documents between
laptops and desktop computers. In a hypothetical scenario, work in the office
is usually performed on a desktop computer, taking advantage of its greater
processing power and additional resources. At the end of the day (or the beginning
of that business trip), all the work performed on the desktop computer needs
to be transferred over to your laptop.
Conversely, while at home (or on the road), changes are made to various documents.
When returning to the office, all changes made to documents on the laptop will
need to be copied to the desktop machine, in order to avoid accidentally modifying
an out of date file.
The first step in providing a solution for this scenario is to establish connectivity
between the two computers. This simply means that the two computers must be
able to physically exchange information before synchronization can occur. There
are usually several ways to do this, and the exact method you use depends upon
your hardware configuration. Plugging into a network via an ethernet cable is
probably the most popular. Some computers are also equipped with infrared ports
that allow a wireless connection. A popular method of late is the use of Apple's
AirPort device to achieve wireless connectivity.
Regardless of the physical connection method, one of the two computers will
have to be setup to allow the other to share files. This is simply called enabling
file sharing. Either computer can have file sharing enabled, but it is usually
best to do so on your desktop machine. To enable file sharing, launch "System
Preferences" from the Dock and choose "Sharing" from "Internet & Network" group.
The status of file
sharing is displayed at the top of the File & Web tab panel. If file sharing
is off, turn it on by clicking the "Start" button in the File Sharing group.
You probably want to make sure your computer has a meaningful name before doing
so. Note that once file sharing is turned on, it will remain on, even between
restarts of the computer. The only way to turn it off is to revisit the Sharing
preferences panel and turn it off.
The next step in achieving connectivity is to connect to your shared computer.
In this example, you will be doing so from your laptop. To do this, switch to
the Finder and choose "Connect to Server" from the "Go" menu.
A list of all available
computers should appear in the "Local Network" group, among which should be
your desktop machine. Select it and click "Connect". You will be prompted for
a name and password. You should use the same name and password used on the desktop
machine as your local user. This ensures you have access and privileges to your
local documents. After doing this, a new icon will appear on your desktop. This
icon represents the shared files on your desktop. You can open it and navigate
the files, just as if they were stored on your laptop.
Now that connectivity has been achieved, it's time to setup a Synchronizer Document
that will automate the synchronization for you. The first step is to decide
which computer will be responsible for the synchronization. It is highly recommended
that this computer be the one that has to connect to the other. Doing so will
save you a step by automatically connecting to your shared computer (as we mention
later). In our example, you should use your laptop.
Launch ChronoSync. A new Synchronizer Document will be automatically created
for you. First, choose your local target by clicking the "Choose" button in
the "Local" group of the Targets Tab Panel. Use the file selection dialog to
locate the folder on your laptop that contains the documents you wish to synchronize.
Next choose your remote target. This will be the folder on your desktop with
which you will be synchronizing. Click "Choose" in the "Remote" group and navigate
to the folder on your desktop machine. You will likely have to scroll the file
browser all the way to the left to see your desktop machine listed as a disk
volume. Click it and begin your navigation from there.
The next step involves establishing the synchronizing direction. ChronoSync
defaults to the "Upstream" synchronization direction. This is deemed the safest
setting and hence it is used by default. For laptop <-> desktop synchronizations,
however, you will usually want this to be "Bi-directional". This way, modifications
made to files on either computer will get copied to the other machine. To enable
bi-directional synchronization, simply click the "Bi-directional" radio button
in the Options drawer.
You are now pretty much ready to perform your synchronization. Before you do
so, however, you should save the Synchronizer Document. This document will save
the settings you've just made, thus alleviating the burden of specifying them
each time you need to synchronize. To do this, just choose "Save" from the Toolbar.
Choose a location on your local hard drive where you can readily find it. The
"Desktop" may be a good choice. Also, give it a meaningful name like "Sync with
my desktop computer".
When this is all done, go ahead and click "Synchronize" in the Toolbar. An analysis
begins, comparing all the files in your local and remote target. After it is
determined what files need to be copied, synchronization will begin. Depending
how many files there are, this may possibly take a long time. The good news
is that, unless you make massive changes to documents when the two computers
are apart, the first synchronization is the longest one you'll ever perform.
This is because from now on, only the files that actually change will be synchronized.
After your first synchronization is performed, you will want to experiment and
see how each successive synchronization will occur. This first step is to quit
ChronoSync. Next, disconnect from the shared computer. This is called unmounting.
To do this, select the icon of the shared computer on your desktop and choose
"Eject" from the Finder's "File" menu. This can also be achieved by dragging
the icon to the trash in your Dock (the trash can changes to an "Eject" icon
when doing so).
Once you've performed these steps, your computer is basically in the same state
it would be when you first come into the office. Locate the Synchronizer Document
you created and double click it. If you disconnected from the shared computer
as instructed, the first thing that ChronoSync will do is to try to reconnect
to it. During this process, you will likely encounter the following dialog:
This allows you to enter your user name and password in order to gain access to the computer to which you are connecting. This security measure ensures that someone without authorization can't use your laptop to connect to your desktop machine. While security is good, in some circumstances, it really isn't important and becomes more of a burden. Luckily, you can circumvent this behavior by clicking "Options..." from the login dialog. The following appears:
From here, you would
probably want to click "Add Password to Keychain". This will add the name and
password you use to your local user's keychain. The behavior of your keychain
can be controlled by using the Keychain Access utility that comes with Mac OS
X. Usually you don't need to mess with your keychain configuration however.
All you need to know is that by adding your name and password to the keychain,
you will never have to type it in again.
Now that you've done all this, how will you actually use ChronoSync on a daily
basis? Given the scenario we've been discussing, here's how: At the beginning
of the day, you show up at the office and connect to your network using the
usual means (ethernet, infrared, AirPort, etc.). Boot up both your laptop and
desktop. After booting is complete, double click the "Sync with my desktop computer"
Synchronizer Document on your laptop that you previously created. A connection
will automatically be made with your desktop. After this, simply click "Synchronize".
When the process completes, you can quit ChronoSync and proceed with your busy
day.
At the end of the day, assuming your laptop is still connected to the network,
just repeat the process - double click "Sync with my desktop computer" and click
"Synchronize". Any changes made to documents on either machine will be synchronized.
As long as you begin and end the day with this procedure, all will be well.
Synchronizing files between a laptop and desktop computer is essentially the
same as connecting to a file server - the shared computer is simply acting as
a file server. You thus may want to read the following sections to gain insight
into the process.