I'm just trying to understand why this simple scenario didn't work as I expected... I have a job configured as follows:
1. Mirror "C:\Some Folder" to "A:\Some Folder Backup"
2. Mirror A:\ to B:\
3, 4, 5... Some other drive Mirrors.
Before the job I created empty folder "A:\Some Folder Backup".
This job ran for the first time last night, and "A:\Some Folder Backup" has all of the expected contents, but "B:\Some Folder Backup" is an empty folder.
If this was respecting the job order, shouldn't the folder in B:\ have all of the same contents that it does in A:\? How could this happen?
Note that I do currently have "Use database to detect file changes" enabled for all of these folder pairs.
Thanks!
Jake
Understanding Copy Order
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You have a (partial) overlap between one or more sync locations in your left-right pairs: "A:\Some Folder Backup" of pair 1 is part of A:\ of pair2.
Such overlaps can cause unexpected sync results, as you experienced. FFS warns you about such overlaps, unless you disabled that warning.
FreeFileSync (FFS) does not first perform a Compare and then Sync of left-right pair 1, and then a Compare and Sync of left-right pair 2, etc.
Instead, FFS first performs a Compare of all left-right pairs, determines the required sync actions, an only then (as per the Compare results) performs the Sync on all left-right pairs.
Because "A:\Some Folder Backup" is not synced with "C:\Some Folder" yet at the time of the Compare, the Compare of A:\ to B:\ is unaware of any changes that will be made to "A:\Some Folder Backup" during the sync, so plans no sync actions from A:\ to B:\ for changes made to "A:\Some Folder Backup" during the "C:\Some Folder" to "A:\Some Folder Backup" Sync following that Compare.
Only during the next FFS Compare+Sync run, such changes to "A:\Some Folder Backup" will be synced to B:\
Such overlaps can cause unexpected sync results, as you experienced. FFS warns you about such overlaps, unless you disabled that warning.
FreeFileSync (FFS) does not first perform a Compare and then Sync of left-right pair 1, and then a Compare and Sync of left-right pair 2, etc.
Instead, FFS first performs a Compare of all left-right pairs, determines the required sync actions, an only then (as per the Compare results) performs the Sync on all left-right pairs.
Because "A:\Some Folder Backup" is not synced with "C:\Some Folder" yet at the time of the Compare, the Compare of A:\ to B:\ is unaware of any changes that will be made to "A:\Some Folder Backup" during the sync, so plans no sync actions from A:\ to B:\ for changes made to "A:\Some Folder Backup" during the "C:\Some Folder" to "A:\Some Folder Backup" Sync following that Compare.
Only during the next FFS Compare+Sync run, such changes to "A:\Some Folder Backup" will be synced to B:\
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Thanks for the explanation, that makes sense!
I managed to implement this by splitting the job with overlap into its own ffs_batch, and then I created a batch script that runs both of the ffs_batch files in succession. It seems to be working really well.
I managed to implement this by splitting the job with overlap into its own ffs_batch, and then I created a batch script that runs both of the ffs_batch files in succession. It seems to be working really well.
