Starting w/ 2 identical profiles

Is it possible to start with 2 computers which have the exact same profiles (one a Time Machine Backup of the other), then share the relevant folders of each? Will SyncThing realise that the contents are the same to start, then start copying over changes from that point on?

It depends…

The two profiles will contain the same Syncthing configuration files, which means they’ll also have the same Syncthing device ID, causing a conflict.

As to if Syncthing will merge the contents of a pair of linked folders between two devices, yes.

Good point. I should have specified, that they would be identical before I install SyncThing.

For your second answer, this means they will not create duplicates of each file? Or worse, delete everything…

Syncing Time Machine backups may or may not work as you expect, there is funny stuff going on in there with the filesystem (directory hard links).

I’m not trying to sync the backups. I am creating two identical computers, then choosing certain folders to sync after that: Desktop/Documents/Downloads

For your other answer, this means they will not create duplicates of each file? Or worse, delete everything…

Indeed it should be fine. If you want to be sure, set one side to “send only” at the start of the experiment, and once they have both scanned are in sync (or not), hit override. You might expect changes to be reported (timestamp differences etc) but they should be resolved without duplicates, unless the contents of the files are also different.

Thank you. Sounds like override means two-way talk. I’ll look into that.

I saw some helpful information about syncing when one is not on the same network on Tech Craft’s YT video. Is there specific documentation?

See:

There are also a bunch of earlier forum threads discussing various network scenarios including using VPNs, CGNAT, etc.

Thank you. VPN is a key issue.