Using robocopy to backup files to a D-Link DNS-321


I use robocopy to back up my music collection to my D-Link DNS-321. I use the /xo switch so only new and modified files would be copied – like so:

robocopy c:\music\music z:\music /E /xo

However, it was taking forever because every file was considered “NEWER” than the existing backup copy. At first, I thought my music program (Media Monkey on Windows) was updating the mp3 tags or touching the files. That turned out to not be the case.

Instead, the issue was a difference in precision between timestamps on my laptop (Windows XP) and the DNS-321 (Linux/Samba).

The solution? The /fft switch:

robocopy c:\music\music z:\music /E /xo /fft

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