Setting up in a LAN with Internet granted to one machine only

Hello,

I try to run Syncting on a Win10 computer. A gateway prevents it to reach the net. I want to sync with a Win7 computer on the same LAN, which has Internet access.

On the Win7 machine, it runs fine. Unfortunately on the Win10 machine, the system daemon quits before I can do anything.

Here are the logs:

[monitor] 12:38:54 INFO: Log output saved to file "C:\Users\Myself\AppData\Local\Syncthing\syncthing.log" [start] 12:38:55 INFO: syncthing v1.18.1 "Fermium Flea" (go1.16.6 windows-amd64) teamcity@build.syncthing.net 2021-07-30 12:41:57 UTC [start] 12:38:56 INFO: Couldn't fetch release information: Get "https://upgrades.syncthing.net/meta.json": dial tcp: lookup upgrades.syncthing.net: getaddrinfow: The requested name is valid, but no data of the requested type was found. [start] 12:38:56 INFO: Initial automatic upgrade: no version to select [PUSHH] 12:38:56 INFO: My ID: PUSHTAH [PUSHH] 12:38:57 INFO: Single thread SHA256 performance is 75 MB/s using crypto/sha256 (74 MB/s using minio/sha256-simd). [PUSHH] 12:38:57 INFO: Hashing performance is 68.25 MB/s [PUSHH] 12:38:57 INFO: Overall send rate is unlimited, receive rate is unlimited [PUSHH] 12:38:57 INFO: Relay listener (dynamic+https://relays.syncthing.net/endpoint) starting [PUSHH] 12:38:57 INFO: Using discovery mechanism: IPv4 local broadcast discovery on port 21027 [PUSHH] 12:38:57 INFO: Using discovery mechanism: IPv6 local multicast discovery on address [ff12::8384]:21027 [PUSHH] 12:38:57 INFO: TCP listener ([::]:22000) starting [PUSHH] 12:38:57 INFO: QUIC listener ([::]:22000) starting [PUSHH] 12:38:57 INFO: Relay listener (dynamic+https://relays.syncthing.net/endpoint) shutting down [PUSHH] 12:38:57 INFO: listenerSupervisor@dynamic+https://relays.syncthing.net/endpoint: service dynamic+https://relays.syncthing.net/endpoint failed: Get "https://relays.syncthing.net/endpoint": dial tcp: lookup relays.syncthing.net: getaddrinfow: The requested name is valid, but no data of the requested type was found. [PUSHH] 12:38:57 INFO: Relay listener (dynamic+https://relays.syncthing.net/endpoint) starting [PUSHH] 12:38:57 INFO: Relay listener (dynamic+https://relays.syncthing.net/endpoint) shutting down [PUSHH] 12:38:57 INFO: listenerSupervisor@dynamic+https://relays.syncthing.net/endpoint: service dynamic+https://relays.syncthing.net/endpoint failed: Get "https://relays.syncthing.net/endpoint": dial tcp: lookup relays.syncthing.net: getaddrinfow: The requested name is valid, but no data of the requested type was found. [PUSHH] 12:38:57 INFO: Relay listener (dynamic+https://relays.syncthing.net/endpoint) starting [PUSHH] 12:38:57 INFO: Relay listener (dynamic+https://relays.syncthing.net/endpoint) shutting down [PUSHH] 12:38:57 INFO: listenerSupervisor@dynamic+https://relays.syncthing.net/endpoint: service dynamic+https://relays.syncthing.net/endpoint failed: Get "https://relays.syncthing.net/endpoint": dial tcp: lookup relays.syncthing.net: getaddrinfow: The requested name is valid, but no data of the requested type was found. [PUSHH] 12:38:57 WARNING: Failed starting API: listen tcp: lookup localhost: getaddrinfow: The requested name is valid, but no data of the requested type was found. [PUSHH] 12:38:57 INFO: QUIC listener ([::]:22000) shutting down [PUSHH] 12:38:57 INFO: Detected 0 NAT services [PUSHH] 12:38:57 WARNING: Starting API/GUI: listen tcp: lookup localhost: getaddrinfow: The requested name is valid, but no data of the requested type was found. [PUSHH] 12:38:57 INFO: UPnP parse: dial tcp 192.168.1.1:1900: operation was canceled [PUSHH] 12:38:58 INFO: TCP listener ([::]:22000) shutting down [PUSHH] 12:38:58 INFO: Exiting

Thanks for you help.

It’s exiting because it can’t start the GUI/API, because “localhost” is apparently not a thing on this computer. That said, our default listen address is 127.0.0.1:8384 which doesn’t require looking up localhost, so I guess something is non-default here, or maybe the Go HTTP server wants to look up localhost for some other reason. In any case, not having a localhost is unusual and I’m not surprised it breaks. Perhaps you need to be less strict in what “not granted internet” means.