Backup solutions for large networks or workgroups are two-a-penny on Linux, but if you just want to back up a couple of folders with your personal data or keep a backup copy of this data in sync, legacy backup tools are often oversized and thus not fit for the purpose. A small Qt application named Synkron [1] steps into the breach and has custom features with enough potential to keep datasets from different sources in sync at all times.

Uncomplicated

Synkron can be installed from the software repos of virtually all major KDE-based distributions; after installation, you will see a launcher in the Utilities | Archive menu. Arch Linux and derivatives such as Manjaro or Antergos also have Synkron in the AUR [2]. If your distribution does not offer the program, the source code is available for downloading from the project website.

The first time you launch the software, you are taken to a clear-cut program window in which the most important, central element is two input areas for path details. You can enter the two folders you want to sync here; pressing the Browse button to the right gives you an easy way to do so.

The program's most important selling point is its tab structure, which lets users create multiple synchronization profiles and process them in parallel. For a simple sync option, the software starts to synchronize your data when you press the Sync button at the bottom right in the program window. The process steps are shown in a sync log in the lower pane of the window.

Some of the steps are color highlighted: For example, if the program fails to open a folder, the error messages are shown with a red background, whereas successful completion of a synchronization run is visualized in green (see Figure 1).

Figure 1: Logging the synchronization activity.

For a view of the successfully completed tasks, press the Analyse button, which reports the errors that occurred with individual files during a backup.

Complex Searches

Besides simple backups, Synkron also lets you define exclusion criteria or special instructions for the sync action; this avoids saving all the files and folders in a tree. To define these criteria, press the Advanced button at the bottom left in the window.

In the context menu that now appears, you can check boxes to select various options, such as excluding empty directories from the sync. You can also prevent recursive synchronization, and if you want to include or exclude hidden files and directories, you can check a box to do just that.

Blacklist

If you want to exclude individual files or directories from the sync process as a general rule, you can do so in a clear-cut way. To open the list window, press the Blacklist button in the button bar at the top. In the three-pane window, you can now define the data to exclude by pressing the Add button. Synkron then asks you for the file names and paths, and you can again use a file browser to select them.

If you want to exclude files with a specific extension independent of their positions in the tree, you can add this suffix in the Extensions in the blacklist: pane. Synkron then avoids syncing files with the selected suffix. You need to enter the suffix in the dialog box as .<ext> (e.g., .raw) – that is, without a wildcard.