TOS 7 Feature Request: TFM Backup — Multiple Source Folders in a Single Backup Task with Sequential Execution

[Tolian]

Application: TFM Backup
Operating System: TOS 7
Hardware: TerraMaster U4-500

Hello TerraMaster Team!

I would like to suggest an improvement to TFM Backup: the ability to select multiple independent source folders within a single backup task, with support for mirror synchronization and sequential execution.

Although this may seem like a relatively small improvement, the current limitation creates significant difficulties when organizing backups to a single destination, particularly an external USB drive.

1. Description of the Problem

Currently, TFM Backup allows users to create separate backup tasks for different folders, but it does not allow multiple independent source folders to be combined into a single task.

For example, I have a TerraMaster U4-500 NAS running TOS 7, and I want to regularly create mirror backups of the following folders to a single external USB drive:

• /Volume1/Documents
• /Volume1/Photos
• /Volume2/Projects
• /Volume3/Archives

Each folder should be synchronized to its own destination folder on the USB drive, preserving its directory structure.

Currently, this requires creating four independent TFM Backup tasks.

The main problem is not the number of tasks, but the inability to guarantee their sequential execution.

2. Why Separate Backup Tasks Are Not an Adequate Solution

Backup duration is unpredictable and constantly changes depending on the amount of modified data.

For example:

• The first task may finish in 10 minutes today but take several hours tomorrow because a large number of files have changed.
• The second task should start only after the first task has finished.
• The third and fourth tasks must also use the same USB drive sequentially.

If these tasks are scheduled to start at different times, there is no guarantee that the previous task will have finished before the next one begins.

This creates two undesirable situations.

Situation 1: Multiple backup tasks running simultaneously

If one task is still running when another scheduled task starts, multiple backup processes begin accessing the same physical USB drive simultaneously.

This can cause:

• Significant performance degradation due to competing disk I/O operations.
• Increased load on the storage device and NAS.
• Unpredictable increases in the execution time of all running tasks.
• Potential backup failures, particularly when system resources are limited or I/O errors occur.

Consequently, it becomes impossible to guarantee that all backup tasks will finish within the available backup window.

Situation 2: Excessively long intervals between tasks

To avoid simultaneous execution, users can schedule separate tasks with large time intervals between them.

However, this introduces additional problems:

• The entire backup process takes significantly longer than necessary.
• The USB drive remains idle while waiting for the next scheduled task.
• It becomes difficult to complete all backups within a single overnight backup window.
• If the amount of modified data increases significantly, the existing schedule may become unsuitable again.

Therefore, creating multiple independent tasks is not an adequate solution.

This problem is especially relevant when using external USB drives, where available I/O performance is limited and sequential access may be preferable.

3. Proposed Solution

I suggest adding the ability to configure multiple independent source-destination folder pairs within a single TFM Backup task.

For example:

Code: Select all

Source                  Destination
----------------------------------------------------
/Volume1/Documents  ->   USB/Backup/Documents
/Volume1/Photos     ->   USB/Backup/Photos
/Volume2/Projects   ->   USB/Backup/Projects
/Volume3/Archives   ->   USB/Backup/Archives

Only one schedule would be required for the entire backup task.

TFM Backup would process the selected folders sequentially, starting the next synchronization operation only after the previous operation has completed.

This would eliminate unnecessary competition between backup operations for access to the same destination drive, regardless of how long each individual folder takes to synchronize.

4. Additional Suggested Features

Ideally, this functionality could include the following capabilities.

4.1. Multiple Sources and Destinations

A single backup task should support multiple source-destination folder pairs.

Source folders could be located on different internal NAS volumes, while their destination folders could be located on the same external USB drive.

4.2. Sequential Execution

Users should be able to select sequential processing as an execution mode.

The next folder would be synchronized only after the previous folder had been processed, according to the configured error-handling policy.

This would allow more efficient use of the destination drive's available I/O performance.

4.3. Independent Mirroring Settings

Ideally, each source-destination pair could have its own backup mode.

In particular, mirror synchronization should support deleting destination files and directories that no longer exist in the corresponding source folder.

Importantly, deletion operations must be strictly limited to the destination directory associated with the relevant source folder.

Other backup directories must remain unaffected.

4.4. Error Handling and Task Continuation

If an error occurs while synchronizing one folder, it would be useful to offer configurable behavior:

• Stop the entire backup task.
• Skip the problematic folder and continue processing the remaining folders.
• Retry the failed operation a configurable number of times.

An especially important safety requirement: temporary unavailability of a source directory must never result in the accidental deletion of its existing mirror backup.

4.5. Unified Logging and Statistics

A single backup task should have a unified execution log containing detailed information about each source-destination pair.

Useful information would include:

• Synchronization start and completion times.
• Number of copied, updated, and deleted files.
• Total amount of data transferred.
• Average transfer speed.
• Errors and final execution status.

This would simplify backup monitoring and troubleshooting.

4.6. Destination Drive Availability Verification

For backup tasks using external USB drives, it would be useful to verify the availability of the destination drive before starting synchronization.

If the drive is disconnected, not mounted, or not writable, the backup task should terminate with an appropriate notification.

Ideally, TFM Backup could also verify the destination drive's UUID or another persistent identifier to prevent accidental backups to an incorrect device.

5. Expected Benefits

The proposed functionality would allow users to organize backups of multiple independent folders within a single task and a single backup window.

Users would no longer need to estimate the duration of each individual backup, configure artificial delays between tasks, or worry about multiple backup processes simultaneously writing to the same USB drive.

Additionally, a unified backup task would significantly simplify scheduling, monitoring, error handling, and reviewing backup results.

Of course, sequential processing of multiple folders should not be limited to external USB drives. It would also be useful for other destination types supported by TFM Backup.

In my opinion, support for multiple source folders with sequential execution is an important capability for a complete backup solution, especially when multiple source directories must be regularly synchronized to a single physical storage device.

I hope the TerraMaster development team will consider implementing this functionality in a future version of TFM Backup.

Thank you for your continued work and for improving TOS 7!

[TMroy]

From what you've described, you'd want Duple Backup rather than TFM Backup. TFM stands for TerraMaster Folder Mirror — it's mainly meant for mirroring folders. Duple Backup should do what you need.

[Tolian]

From what you've described, you'd want Duple Backup rather than TFM Backup. TFM stands for TerraMaster Folder Mirror — it's mainly meant for mirroring folders. Duple Backup should do what you need.

Hello,

thank you.
Duple Backup is just what I needed! Fast, convenient, and high-quality.

Best regards.