Incremental backups copy all SQL .bak files every backup

I am using Microsoft SQL Server’s internal backup mechanism to create backups of the SQL databases. I keep the last seven .bak files for each database. Each of these large files is copied into the urbackup_tmp_files folder each time a UrBackup incremental backup runs even though only the latest .bak file will have changed. Is this expected or does Urbackup only copy changed files during incremental backups?


It probably renames the files? In this case if you are not doing the backups with the internet mode or “client side hashes” are not enabled it will re-download the file only to notice later it is the same one.