Sync.ffs_db questions

[mfreedberg]

Hello again!
Given that we are using the Automatic option for our backups, every directory
in the pair structure will have its own sync.ffs_db file to manage the file
changes, which brings me to two questions.

1. Can you confirm that by default the sync.ffs_db file has the Hidden attribute set?
2. What is the impact of deleting the sync.ffs_db file from a local directory? Does that mean that FreeFileSync loses data it needs to track and reconcile things like file renames and moves with the target directory? What does FreeFileSync do in the case where a local directory no longer contains the sync.ffs_db?

Thanks again and I appreciate the time you take to answer our many questions.

[Zenju]

> 1. Can you confirm that by default the sync.ffs_db file has the Hidden
attribute set?
Yes, this is the behavior on Windows. On Linux the file will be named
".sync.ffs_db" which has a similar effect depending on file manager settings.

>What is the impact of deleting the sync.ffs_db file from a local directory?
FFS will behave like on the very first automatic variant synchronization:
Files exising on one side will be copied to the other, newer files are copied
over older files. After sync one database file is updated the other you
deleted is re-created normally. However the one file you did not delete will
now carry some obsolete information referring to a partner database file not
existing anymore. Considering that the database files are very small this
redundancy should not be noticable with regards to perf.

[mfreedberg]

Thank you for the detailed response, that all makes good sense to me.

In the case above, does the code update the remaining sync.ffs_db to reflect a
new partner database file or does it continue to reference an obsolete
database (and with no ill effects)?

[Zenju]

The update just adds a new database entry after detecting this is the first
sync between the two folders (or at leaset as it appears with one db file
being deleted). The old database entry will just be unused with no negative
effects.

[mfreedberg]

Thanks, and yes, I have more questions coming...sorry!

[dsmidgy]

Hi, Zenju

Could I ask you another question regarding sync.ffs_db file. If I make a
automatic sync between A (source) and B (target 1), and then between B and C
(target 2), another sync between A and B will be corrupted, right?

Thank you for your help,
Dominik

[Zenju]

You may sync an arbitrary number of folders via automatic mode, "n-way" syncs
are fully supported. Just make sure this is the model you want: any change in
any of the folder will be propagated to all others, that is "shared ownership"
of the data.