Synchronizing files between laptop and network storage with Chronosync

As outlined in the IAC File Storage Overview, we generally encourage users to store files on network storage rather than on local drives for backup and security reasons. However, laptop users, particularly those who travel often, may need full-time access to all files, regardless of whether internet access is available. In such cases we recommend file synchronization solutions, which synchronize local and network storage when the computer is connected to the campus network. This allows access to all files even without internet access while also ensuring that files are copied to network storage and therefore backed up.

Unlike Windows, MacOSX does not include built-in functionality for file synchronization with IAC network storage. We therefore recommend a third-party product called Chronosync, by Econ Technologies. A 30-day product demo is available, and single licenses can be purchased from the Econ Technologies online store for $30-$40. (Discounted volume licenses are available; if a department or group would like to consider that possibility please contact IAC IT staff.)

Econ Technologies distributes the Chronosync installer as a disk image (dmg) file:

To install Chronosync, simply double-click the dmg file. After prompting for license agreement, the disk image will mount and display a window:

Run the installer, accepting defaults as necessary. After installation, you'll then want to configure Chronosync by specifying synchronization targets, or the folders you'd like to keep synchronized. Chronosync stores these and other configuration settings in individual files. When you first open Chronosync (which can be found under the 'Applications' folder), you'll be presented with a new 'Untitled' document. In this case, a user named 'sh157' will configure Chronosync to synchronize his local 'Documents' folder with his network storage. Note that the left target is already defined by default as sh157's Documents folder. To define the right target as the network storage, first mount the network storage. (See how-to documents for Tiger and below or Leopard and above for assistance.) Note in this case that the network volume 'sh157' is mounted on the Desktop to the right of the Chronosync document:

While there are several ways to define the right target, one easy method is simply to drag the 'sh157' network volume into the 'Right Target' area of the Chronosync document. This defines the network volume as the right target:

Chronosync can perform different types of synchronization. In general we recommend that users choose 'bidirectional' synchronization, which synchronizes new or changed files both from local to network and from network to local storage. (Chronosync will flag cases where uncertainly arises about the most recent file version.) With bidirectional synchronization, users can create or modify files either on their laptop or directly on the network (using another computer, for example), and changes will be reflected in both places.

To configure bidirectional synchronization, select 'Synchronize Bidirectional' 'Operation' popup menu (blue arrow). To ensure that an exact copy is maintained in both left and right targets, also check the checkbox for 'Synchronize Deletions' (red arrow). (The default method of handling deletions, 'When deleting files, Move to Archive', stores deleted files in a folder called '_Archived Items' under each target location.):

In a future step we will configure synchronization to occur whenever the network volume 'sh157' is mounted. In such a configuration we will not need Chronosync to attempt to mount the network volume, so we will disable that feature. Click the 'Options' button under the Right Target (red arrow) and uncheck the 'Attempt to Mount Server' checkbox (blue arrow):

Now that we have entered this configuration information, we should save the configuration document by clicking the 'Save' button. In this case the document will be named 'sync-to-network' and saved on the Desktop:

To configure synchronization to occur when the right target (the network volume) is mounted, click the 'Schedule...' button at the top of the document dialog box. From the 'Run Sync' popup menu, choose 'When a Volume Mounts' (image a). In the resulting dialog, under 'When', check 'Right Target Mounts' (image b, blue arrow):



With this configuration, when the network volume is mounted in the future, Chronosync will perform a bidirectional synchronization. This will generally take place in the background, though making Chronosync the active application will display the 'Scheduled Documents Manager', which shows synchronization progress. Image a shows 'Scanning', when Chronosync compares files in each location to determine necessary changes. Image b shows 'Running', when changes are in progress:


a:   b:

Note that when performing an initial synchronization, it is usually best for the laptop to be plugged into the faster wired campus network rather than on LAWN, especially when there is a large amount of data to be synchronized.

Chronosync's default behavior is to create a new, untitled document every time it is started. This behavior may be somewhat confusing or bothersome, and it can be changed within Chronosync from the Chronosync->Preferences menu item. Uncheck the 'Create new document on activate' checkbox:

A Chronosync menu item appears at the top right of the MacOSX menu and allows easy access to open Chronosync and to control scheduled synchronizations: