Backing up an external (USB) mounted media on Windows: Incrementals faked?!

> Backup of external media need some specific setup?

I've changed the subject because was totally misleading; but still i need
some clue...


I need to backup an external, USB, disk mounted on a Win10 client; disk
contain 8TB of data, scattered in many files/dirs. I'm using progressive
virtual full, so i'm using 'accurate = yes'.

I've tried with default fileset options, then with 'accurate = sm' but for
both, sooner or later (i supposed when the client get rebooted; or usb bus
reset and disk get umounted/remounted) i get an incremental backup of the
size of a full (8TB), so simply *ALL* files are considered modified by
bacula.


I've tried 'accurate = s5' and incremenetals seems behave right, but an
incremental took more or less a day to complete. Too slow...

I coud try 'accurate = s' but i think is is unacceptable... too risky...


There's some 'knob' to play with? Windows side (eg, prevent to alter/fake
modification time on remount) or bacula side?


Thanks.

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