FAQ and Knowledge Base

File Synchronization (a.k.a. File Sync) is the process of ensuring that two or more locations contain the same, up-to-date, files. If you add, change, or delete a file from one location, the synchronization process will add, change, or delete the corresponding file at the other location.

Synchronization can be “two-way” or “one-way”.

Two-Way Synchronization (a.k.a. bi-directional synchronization or both-ways synchronization):

This synchronization process copies files in both directions to reconcile changes as needed. Files are expected to change in both locations. The two locations are considered equivalent.

Example: if a file is newer in Location A, it will be copied to Location B. But if a file is newer in Location B it will be copied to Location A. Similarly, if a file is deleted from Location A, it will be deleted from Location B as well and vice versa.

One-Way Synchronization (a.k.a. file mirroring / file replication / file backup):

Files are expected to change in one location only. To reconcile the changes, the synchronization process copies files only in one direction. The two locations are not considered equivalent. One location is considered the Source and the other is considered the Target. Files are pushed from Source to Target (or files are pulled from Source to Target, but always in one direction only). Source is said to be mirrored to Target.

This creates an exact 1:1 replica of all files in Source to Target. This is very useful and effective for backup purposes since only changed/new files are copied.

Example: If a file is newer in Location A (Source), it will be copied to Location B (Target). But if a file is newer in Location B, it will NOT be copied to Location A. Similarly, if a file is deleted from Location A, it will be deleted from Location B. But a file deleted in Location B is restored using the file in Location A.

 ViceVersa PRO supports several One-Way and Two-Way Synchronization methods: see List of File Synchronization, Backup and Replication Methods Supported by ViceVersa

About Visual Synchronization (Side-by-Side)

With ViceVersa you can synchronize files visually. ViceVersa will compare and analyze the files and folders in two or more locations and show you the files side-by-side, with all the changes that happened since last synchronization clearly marked. Show Me

Automatic Synchronization

File synchronization can be run automatically, without user intervention, at intervals (i.e. every 10 mins, every 2 hours, etc.), scheduled (i.e. Monday and Friday at 7:00), real-time (i.e. as soon as file changes are detected), at startup or at shutdown.

Common Synchronization Scenarios

• Synchronization between computers connected to the local network (LAN). Computers can be laptops, desktops, workstations, servers. Selected folders across computers are shared, using Windows File Sharing, and synchronized using ViceVersa.

• Synchronization between computers connected to the Internet (WAN). This requires a VPN tunnel. Computers can be laptops, desktops, workstation, servers. ViceVersa is used to synchronize files over VPN.

• Synchronization between computers and external (USB) drives.ViceVersa is used to synchronize files to USB devices.

• Synchronization between computers and NAS.ViceVersa is used to synchronize files to NAS devices.

• More Scenarios

The end-goal is to make sure that the selected folders on computers and/or drives have the same, most current files.

Synchronization Between Non-Connected Computers

For computers that are not connected to a network, synchronization can be achieved by using a portable USB drive.
If there are files on a computer at home (PC-1) that must be kept synchronized with files on  a computer at work (PC-2), synchronization can be achieved by synchronizing PC-1 versus a portable USB drive and then taking the drive to work and performing the same synchronization between PC-2 and the portable USB drive.
At the end of the process the same up-to-date files will be on both PCs (and on the USB drive, useful for data backup purposes). Read More

Additional Features

ViceVersa PRO provides an extensive set of options that allow you to control and customize the synchronization process in detail. Here are some examples:

• File Archiving. During synchronization, older files (in Source and/or in Target) are not simply overwritten with newer files. Instead, they are moved to an archive location for archiving purposes. Learn More

• File Verification. ViceVersa calculates the CRC value of a file and compares it to the CRC value of the corresponding file in the other location. If the CRC values differ, the files differ. This ensures that files are copied properly. Learn More

• File Encryption. ViceVersa can keep files in Source and/or Target encrypted. This is especially important when copying files to an external USB drive or over the Internet. Learn More

• File Compression. ViceVersa can keep files in Source and/or Target compressed to save space, e.g. on a USB drive or a NAS. Learn More

• Copy Open Files. ViceVersa can copy files even if they are open and in-use (e.g.  Documents, Spreadsheets, E-Mails, Music, etc.). ViceVersa uses the Windows Volume Shadow Service for this. Details

• Bandwidth and Processor Load Control. You can control the bandwidth used and the max processor load to prevent overloading your system while copying files. Details

• Real-Time Backup, Synchronization and Replication. ViceVersa PRO can backup, replicate and/or synchronize your files continuously, as they are being modified. Files can be saved to another location, such as another computer, a network drive, a USB drive, or even another folder on the same computer. Read More

Further Reading

Common Solutions ViceVersa Provides
Copy / Backup Open Files and Databases Using the Volume Shadow Service
VVEngine: Advanced Scheduling