Two instances, one works and the other doesn't

I had a Synchting instance on device 1 on Linux. It used to sync with Synchting in device 2 just fine, both devices are inside a private LAN (or NAT).

I created user 2 in device 1 running an instance of Synchting. I took sudo privilege from user 1 (user 2 has sudo privilege).

The instance for user-2/device-2 syncs with device 1 just fine, but the instance user-1/device-2 longer syncs.

All discovery methods are ON, except for relaying. The devices find each other according to the logs. The dysfunctional instance shows up as “Up to Date” ar transmitter side but stucks at “Syncing 40% (10 MB)” at the received side. All other settings apparently are the same for all instances.

Any idea what might be the problem?

How can I delete an instance and reinstall it?

Please post screenshots from both sides showing the problem.

I try to take pictures when I get to the server.

How to uninstall a particular instance (not the whole synchting)?

I am not sure what you mean.

Syncthings state is stored in syncthings home directory, which is what I assume you refer to as “instance”. Depending on how you installed it, how you are running it, it can be in different places.

If I type “syncthing” on a linux shell, Synchting runs /bin/syncthing and prints that the GUI is available at 127.0.0.1:8384. It opens two TCP ports listening (together with 2–5 UDP ports that seem to be outgoing in my opinion). That’s an instance.

If I switch to another user and do the same thing, the same steps are performed but the GUI would accessible at a different port, say, 1234, with different set of listening ports. That’s the second instance.

The term “instance” is also used by the output of the Synchting in stdout.

The instance run by user with admin rights syncs, whereas the instance run by the non-privilege user does not sync.

So the question is, how to uninstall Synchting for one user and keep it for another? By installing again I hope that it would sync for both users. Otherwise I just uninstall both instances system-wide and start over again (back up device IDs etc).

Everything local to an instance is stored in ~/.config/syncthing unless you specified something else manually.

If I delete ~/.config/synchting directory, and type synchting, would it be regenerated with a fresh install with new keys? I then share the device ID again.

Yep