Understanding the Syncthing - NAS combination

General
1

Hi, I recently started using Syncthing on a Raspberry Pi, my Fedora laptop and Android phone. It works very well, I’m happy with it.

What I don’t understand is how people use it on a NAS. I would guess data on a NAS is often big directories with (for instance) movies or pictures or old accounting files. If you would use Syncthing for that, all those movies and pictures would also be on you computer, which is not useful. Or you could not sync those folders, but then what’s the point?

I searched the forum a little, but didn’t know what keywords to use. NAS leads to a lot of different questions…

2

It depends on how you use your NAS I guess. Yes, I do store movies and pictures on my NAS, but also my entire Documents folder. The Documents folder is then synced between a PC, the NAS, another NAS for backup, and some laptops, which all should have a full copy of the Documents folder. At the same time, my Android phone doesn’t need (and actually can’t) have a full copy of the entire Documents folder, which is several hundred Gigabytes in size. As such, it isn’t shared with the phone, though certain subfolders (which the phone does need) are shared with it.

At the same time, the laptops don’t need a full copy of all movies, so the NAS doesn’t share them with them. A key feature of syncthing is that you can share different folders with different devices, so I can sync what I need and don’t sync what I don’t need.

Ignore patterns are also relevant here, if I want a certain folder to be synced, but want to exclude certain files from some or all devices.

The goals of syncing to the NAS in the first place are (for me):

  • Redundancy, as part of a backup strategy (not the backup strategy itself).
  • Having an always-online device, such that devices can sync even if the PC and laptop are not online at the same time.
3

Thanks @Nummer378 , that makes sense. I understand. I backup the Raspberry Pi connected SSD-drive with Vorta/BorgBase.

It would be nice to be able to connect my movie/photo-drive as well, but that’s not how Syncthing is ment to be used I understand (I mean, for then the be able to browse the movies and photo’s from my laptop).
I do have the movie-drive connected, but that’s linked to Jellyfin.

1 Like
4

It looks like you’re referring to a “selective sync” feature where a device “sees” all files, but syncs only some files of a folder (possibly on-demand), but not all the files all the time. Selective sync is indeed an often requested feature, but yeah unfortunately it doesn’t really exist at the moment (except for some workarounds with ignore patterns).

5

Thank you, good to have a correct description of the feature I’m looking for. That’s indeed what I would like. But I’m happy without it as well, for the moment :slight_smile:

1 Like