Am I totally off my nut or what?

[BenThere]

Asustor AS6806
Drive Bays: 6 using Mirror Sync
Drive Set : Archive4 ( Rotation, Drive1-Drive6, 8 TB ea. )
OS : Windows 10

Document Set:
FFS problem Notes 2026-03-08 111525.txt (this document)
FFS-1 Screenshot 2026-03-09 092120.jpg ( says items not existing on source drive, plainly the comparison below shows this is not true)
FFS comparison Screenshot 2026-03-08 113633.jpg
FFS-2 Screenshot 2026-03-09 092120.jpg (Shows files in question reside on both drives)

I am in the process of implementing a new backup system for a mixed handful of computers, Windows, Mac and Linux. The first rotation is almost complete so I started looking into how the second rotation would progress. I put the last disk from the backup set in to verify how the continuation of the backup would progress. I used the last disk so that there would not be too many changes and make it easier to go through,
I took a look at the Compare Report and was shocked that it shows conflicting information and after seeing this report I am concerned with what will happen the next time it is run to update the backup set..

Screenshots FFS-1 & FFS-2 are different line sets within the same report and is the reported state on the following day after performing the sync.

Report :
1. At the beginning of the report, ref. FFS-1, showing no files on the source drive ( item exists on right side only ) and set to delete the files that were just copied to the sync drive?
2. And then in FFS-2, beginning at line 1523, shows the same files listed above, residing on both sides and no action to be taken.

Concerns :
How can both 1. and 2. be true and actionable?
Which action will be taken, delete the existing files and quit,
delete the existing files and then copy the same files back and quit,
delete the existing files and then copy the same files back along with any new files and quit,
or something else?

According to the file totals and actions at the bottom:
2632 Files are equal
879 Files will be created on the right side
178 Files will be updated on the right side
--------------
3689 total files
- 2666 files to be deleted
-------------
1023 files remaining
Now unless I've gone totally bonkers, if this runs according to the information it has presented to me. This set will be totally out of whack.
What am I missing, other than my sanity?

[Plerry]

Per your first left-right pair, you are synchronizing D:\ (left) to the root of Q:\ (right), thereby creating an overlap between your multiple folder pairs. This can cause the sort of problems you are experiencing.
Because D:\ does likely not comprise a (root)folder Data 1 Backup, the data in Q:\Data 1 Backup does not exist in/on D:\, and thus the Mirror sync of D:\ to Q:\( your first pair) will (correctly) delete anything in Q:\Data 1 Backup.

Unless you are using Include and/or Exclude Filter rules, there is a further overlap between your left-right folder pairs, because by syncing D:\ to Q:\, you already sync all the root sub-folders of D:\ to matching subfolders on Q:\ specifically mentioned in your further left-right pairs.

• If you only want to sync the mentioned root sub-folders of D:\ to Q:\,
a) simply delete your first left-right pair (D:\ => Q:\)
OR
b) delete your last four left-right pairs and replace the default Include Filter * (=everyting) by
Macrium Backups
boot
Asustor Settings Backup
BlueIris
and you problems should be solved.

• If you want to sync all of D:\ to Q:\, you either
a) need to sync D:\ to e.g. Q:\D and delete your last four left-right pairs
OR
b) need to add Data 1 Backup to the Exclude Filter

[Plerry]

To add to the above:
Unless you have disabled it, you did receive a warning from FFS to the extent that there was an overlap between one or more of your sync locations, causing above "unexpected" results.

[BenThere]

Thank you Plerry, I'll look into that. It's always nice to have a fresh pair of eyes take a look.
I have been spending too much time in front of the screen lately. Think I need a Vacation, lol.

[BenThere]

Per your first left-right pair, you are synchronizing D:\ (left) to the root of Q:\ (right), thereby creating an overlap between your multiple folder pairs. This can cause the sort of problems you are experiencing.
Because D:\ does likely not comprise a (root)folder Data 1 Backup, the data in Q:\Data 1 Backup does not exist in/on D:\, and thus the Mirror sync of D:\ to Q:\( your first pair) will (correctly) delete anything in Q:\Data 1 Backup.

I now see that I neglected to include some relevant information that may alter your view.
My apologies.

Additional doc set:
Directory Structure Screenshot 2026-03-10 162751.jpg

Drive Connections Screenshot 2026-03-11 142233.jpg (33.85 KiB) Viewed 190 times

Filters Primary Screenshot 2026-03-10 094320.jpg

Filters Primary Screenshot 2026-03-10 094320.jpg (67.01 KiB) Viewed 190 times

Filters D to Q Screenshot 2026-03-10 093747.jpg[/b]

Filters D to Q Screenshot 2026-03-10 093747.jpg (54.59 KiB) Viewed 190 times

All actions are set as Mirror to Q: drive.
Data is on drives D: and W:, 2 different physical drives.

Drive D: is an external drive for Security and Backup Apps, attached to a PC.
Drives Q: and W:(DATA 1) are individual drives within a network attached 6-bay drive system, Asustor AS6806.
Drive Q: Is backup of Drives D: and W: and is changed daily on a 2-week rotation.
Drive W: is destined to house all of data files for the rest of the network machines.

My intent is to replicate the data of these 2 drives, D: and W: to Q: so that I have a rolling set of 2 weeks and a monthly set for 6 months.

The Exclude filters I used:
Primary Filters: (Filters Primary Screenshot 2026-03-10 094320.jpg)
Local Filter D:\ to Q:\: (Filters D to Q Screenshot 2026-03-10 093747.jpg), Only the ( currently 5 ) files in the root of D: are copied to Q:\, all directories are excluded in this Filter .
This was done precisely in an attempt to avoid the situation you noted concerning Q:\Data 1 Backup. At least that was the intention. Did I miss something here?
Yep, vacation definitely needed.
.
The rest of D: is copied to Q:\ as individual root folders, as new folders may be added and some others may be removed/relocated over time. This is the reason for individual folder copies.
D:\BlueIris is the security camera system and writes data as it is created and then is replicated to Q:\ by FFS (actually it will be RTS once everything is worked out).
D:\Macrium Backups and all others are typically written and copied to Q:\ once per day.
Q: drive is to be rotated on a daily basis.

On the first run FFS did as I expected and copied files and folders to Q:.
14:33:47 Info: 3,681 items found |
14:46:58 Info: Synchronizing folder pair: Mirror ->
D:\
Q:\
14:46:58 Info: Creating file "Q:\CCTVNewSyncSettings-1.ffs_batch"
14:46:58 Info: Creating file "Q:\CCTVNewSyncSettings-2.ffs_batch"
14:46:58 Info: Creating file "Q:\MacriumRescue.iso"
14:46:58 Info: Creating file "Q:\rescuepe.log"
14:46:58 Info: Creating file "Q:\Recovery.txt"
14:47:05 Info: Synchronizing folder pair: Mirror ->
W:\
Q:\DATA 1 Backup
and so on. All was good.

Then it all went haywire on the rotation, I just can't seem to get my head around FFS deleting the files it had copied and that still resided on the source drive.
Thanks Plerry!
Arrrggg, I need some sleep.

[BenThere]

To add to the above:
Unless you have disabled it, you did receive a warning from FFS to the extent that there was an overlap between one or more of your sync locations, causing above "unexpected" results.

I did get a warning after it was completed, I don't recall seeing anything before:
Completed with warnings
Warnings: 2
Items processed: 2,123 (474 GB)
Total time: 01:27:54
Errors and warnings:
00:42:32 Warning: The following folders are significantly different. Please check that the correct folders are selected for synchronization.
D:\ <->
Q:\
00:42:32 Warning: Some files will be synchronized as part of multiple folder pairs.
To avoid conflicts, set up exclude filters so that each updated file is included by only one folder pair.
Q:\ 💾 DATA 1 Backup\Images\AI Generated art\Coloring pages\Screenshot 2023-03-01 at 10.31.30 AM.png
Q:\DATA 1 Backup 👓 Images\AI Generated art\Coloring pages\Screenshot 2023-03-01 at 10.31.30 AM.png
Q:\ 💾 DATA 1 Backup\Images\AI Generated art\Coloring pages\Screenshot 2023-03-01 at 10.33.35 AM.png
Q:\DATA 1 Backup 👓 Images\AI Generated art\Coloring pages\Screenshot 2023-03-01 at 10.33.35 AM.png

After reading it was not clear to me what it was trying to convey because each item in the referenced pair was to the same file in the same folder location.

Thanks for your help with this, as I must be getting dense in my old age.

[Plerry]

> Only the ( currently 5 ) files in the root of D: are copied to Q:\, all directories are excluded in this Filter

As per the FFS manual page on Filter rules:

Set *: as the include filter to match all files, but not folders. During synchronization some excluded folders will still be created if needed, but only if they contain at least one non-excluded item, that is, when they are not empty.

The Local Include Filter *: for your 1st pair will still Mirror all files in D:\ to Q:\, not just those in the root of D:\, which means you still have the experienced and described problem with D:\DATA 1 Backup not existing, consistent with the warnings in your log-file.

If you just want to Mirror files in the root of D:\ to Q:\, and none in any of D;\ 's subfolders (other than those specified in your later left-right pairs), for your 1st pair you can use
• a Local Include Filter of simply *
• a Local Exclude Filter of just *\
As this Local Exclude Filter already excludes all subfolders of D:\ and Q:\, there no longer is the need to also explicitly exclude Macrium backups, boot, Asustor Settings Backup and BlueIris

Could it be that you did not receive the warning about the overlap,
"Some files will be synchronized as part of multiple folder pairs.
To avoid conflicts, set up exclude filters so that each updated file is included by only one folder pair",
because you are running the sync as a *.ffs_batch sync, rather than from the FFS GUI?

[Zenju]

You forgot to exclude "\DATA 1 Backup\" for the first folder pair. Also you probably have "ignore errors" active, otherwise you would have seen the warning *before* starting the sync.

[BenThere]

Plerry,
Thank you for the assist, I have made the changes that you recommended and all appears to be functioning as expected.
However I am still getting the error,

16:44:56 Warning The following folders are significantly different. Please check that the correct folders are selected for synchronization.
W:\ <->
Q:\DATA 1 Backup

Which I did somewhat expect copying from a Root to a Sub-directory, with no apparent effect on the process. Will re-visit upon subsequent backups.
Now to expand down the line to cover other machines and test until all are included and verified.
Again, thank you for the assist, I was afraid I would have to shave my head and join a Monastery. ;-)

[BenThere]

You forgot to exclude "\DATA 1 Backup\" for the first folder pair. Also you probably have "ignore errors" active, otherwise you would have seen the warning *before* starting the sync.

Zenju,
Thank you, you are correct, I did have "ignore errors" active and configured for running as a batch.
Much appreciated.

[Plerry]

The warning that folders are significantly different is obviously correct if Q:\DATA 1 Backup is empty at the time you sync W:\ => Q:\DATA 1 Backup sync.
But now you fixed your setup, the files Q:\DATA 1 Backup sync will no longer be deleted by the D:\ => Q:\ sync. So now you should only (have) receive(d) that warning during the first sync, not during any consecutive sync.