Syncthing connecting to a remote tcp server, is it expected?

Hello, a few minutes ago I noticed some unexpected network connections from my computer. netstat -p tells me that Syncthing is connecting to some seemingly random address (, which resets connection if I try to curl it. seems to be a German hosting company. Is this expected? I cannot find references to the said doman name (neither bare domain not fqdn) in the Syncthing sources or issues (github search).

I have not configured synthing to make non-local connections, and because I use it from the Debian repo, it can not self-update.

Configuring Syncthing for local connections only would mean disabling global discovery and relay, which you probably didn’t :wink: ( is one of the servers in the default relay server pool (, so this is expected.

Is it not possible to run Syncthing reliable w/o global discover and relay? Reading the spec on Relay v1 paragraph 4.4.7, I gather that data is transmitted through a third party, which is highly undesirable for me, regardless of the details of encryption used.

You can disable relays and global discovery, but you need to make sure that local discovery is permitted on your network.

You can configure device addresses manually if that does not work.

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You can disable both discovery and relay in Syncthing settings.

I am not even using local discovery in my setup. As long as you have at least one computer in each pair with a fixed IP address, you can just configure Syncthing on the other to connect to it. Of course, the connecting computer should be able to establish a TCP connection to the port Syncthing is listening to, so check firewalls etc.

Thanks a lot for the responses! I do have some fixed IP devices, so I can go that route.

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