All files deleted following a complete resync

[Haiperlink]

I waited a long time for an unlimited sync service like BitTorrent Sync.

I gave it a try to sync my photos from last year between 2 Windows 7 PCs with external harddrives (both in same network).

The original folder ist 130GB and contains 25.000 Files. My external harddrive is not always connected on my main Notebook, so Sync shows that it can't open it. I'm pretty happy, that it recognizes the harddrive as soon as it is connected.

The initial sync via WiFi took 3 days, which is ok for me, because it's just that first there was a break in between and it started to sync where it stopped. I had to stop the sync again just a few GB before the sync was complete. But when I connected the harddrive again this morning, on my second machine all files were moved into the .syncTrash folder and the synchronization started from the beginning.

I'm pretty sure that there were no files changed on the main system.

[GreatMarko]

This will most likely be due to the fact that your external harddrive is removable, and not always connected.

I'm not sure BitTorrent Sync is currently able to distinguish between a removable drive that's been temporarily "removed", and a folder that's been physically deleted - and so to BitTorrent Sync they may both look the same! - Therefore, when you remove/eject a drive, BitTorrent Sync assumes that because it can no longer access the files in that location, they have been physically "deleted"

[Mowd]

In previous thread I saw that btsync will detect the .SyncID. Doesn't it work?

[Disappointed Cat]

I hope it does check the .SyncID, because if not, then a hard drive crash can make it delete everything in the swarm.

[Haiperlink]

Thanks for your answer GreatMarko.

So the only possibility for me is to run sync only if the external harddrive is connected?

Hopefully this will be fixed in the future, because I wanted to sync the photofolders between multiple NAS, but the main folder will always stay on my external harddrive..

[Disappointed Cat]

Why not just set it up on the NAS servers?

[Haiperlink]

I mostly need the photos when I'm travelling (mostly no internet connection). To prevent data loss I have a copy on my local NAS and for offsite copies my NAS and the NAS from 2 friends are synchronized.

[GreatMarko]

In previous thread I saw that btsync will detect the .SyncID. Doesn't it work?

The .SyncID contains the "internal ID", if you will, of that particular folder and is used to identify the folder to BitTorrent Sync - However, the actual "hash" of all the files within the folder (which is what BitTorrent Sync is monitoring in real time) is stored elsewhere (i.e. on Windows it's under %AppData%/Roaming/BitTorrent Sync) ...so if the hash is accessible but the physical source location isn't, BitTorrent Sync could infer that the source files have been "deleted" (rather than them simply being just "inaccessible" at that time)

[fnordsensei]

…the actual "hash" of all the files within the folder (which is what BitTorrent Sync is monitoring in real time) is stored elsewhere (i.e. on Windows it's under %AppData%/Roaming/BitTorrent Sync)…

It seems to me that this would be way more portable if the hashes were stored along with the .syncID. That way, if the files, hashes and syncID disappeared all at the same time, a drive has probably been unplugged. But if the hash and syncID is there, but the file is not, it has probably been deleted.