I am backing up from two Synology NAS folders to a number of other network drives, one-way synchronizing from the NAS to each of the other drives. Generally, this has been working well, but I noticed that, for the last few weeks, there are many more files being copied to the USB drive that is attached physically to the NAS than are being copied to the other drives.
Most of these files are files that have not been added or modified, which, therefore, already are on the backup USB drive. Nonetheless, a portion of the existing files, a different group each time, overwrites the backup drive files that already should be identical. When it does so, the copied file bears an updated time stamp but otherwise doesn't appear changed.
This behavior now is routine and expected. If I run a backup to that drive and immediately run another after it completes, a new group of files is copied in the second sync. That obviously should not be happening right after a completed sync.
The NAS and backup drives both are 8tb RAID 1. The dataset is about 3.5tb. None of the other drives (local USB drives attached to the Windows 10 computer running freefilesync) exhibits the same issues.
Is this a known issue? If not, I can delete everything on the backup drive and copy over from scratch as a new starting point tomorrow, to see if this issue arises again. I appreciate any suggestions.
One-way synchronization not working with one of several drives
- Posts: 6
- Joined: 23 Nov 2017
- Posts: 6
- Joined: 23 Nov 2017
Okay, this is worse than I imagined. I deleted all of the files on the backup drive and then ran a sync from the NAS to that drive. It took a day and a half to create the new set of files on the backup. Immediately after finishing, I ran another sync to confirm that the datasets were identical. Unfortunately, FFS thinks there is nothing on the backup drive and wants to run the entire backup again. I don't know why there's an issue with this drive and none of the other USB drives on the network to which I also back up, but this is not good. I guess I am in the market for another backup app for that drive.
- Posts: 6
- Joined: 23 Nov 2017
I think the problem is that the files that copy over bear a more recent file date than the original ones, which makes them not identical and thus subject to being overwritten. I could compare by file size or content, but I have no idea how that would affect processing time. I am going to delete again and figure out a way to avoid having the timestamp updated in the process.
