Data lost happens in the following scenario:
1. You're using a scale-out backup repository (SOBR).
2. You created at least one backup using Export Backup functionality with the automated retention setting enabled (non-default setting).
3. You deleted the exported backup file manually prior to its retention policy expiration.
In the above scenario, upon reaching the retention policy for the already deleted backup file, and after failing to find the required file, the daily run of the exported backups retention job will erroneously delete the entire repository folder on one of the SOBR Performance Tier extents.
Note: Some supported repository types, for example Windows-based repositories and SMB shares, have safeguards in place which will restrict the entire repository folder deletion. SOBR made entirely of such extents are thus not impacted by this issue. [UPDATE] After testing all supported backup repository types, only SOBR that includes Linux-based or ExaGrid-based extents was found to be affected by the issue.