ACL updates in incremental backup


With an incremental Windows backup file, existing directories do not update
ACL unless other metadata (such as date) changes.


  1. Create the C:\test directory
  2. Create the C:\test\subdir directory
  3. For C:\test\subdir add write rights for the Authenticated Users group
  4. Make backup of the C:\test
  5. For C:\test\subdir add write rights for the Everyone group
  6. Make the incremental file backup of the C:\test direktory
  7. Delete the C:\test directory and restore it from the backup.

The Authenticated Users group from Step 3 will be enabled in the C:\test\subdir directory, but not the Everyone
group from step 5.

Files are not affected by this problem, it only occurs with directories.

Client OS: Windows 2012 R2
Client: 2.2.6
Server: 2.2.10 (LXC container with Ubuntu Linux, BTRFS)


Correct, it unfortunately uses the last modified time to determine if a directory changed.
I’ll change it such that is uses the USN, like for files. That should fix the issue.