This is basically a continuation of https://forum.syncthing.net/t/stalled-transfers-with-one-device-shows-as-connected-and-the-other-as-disconnected/16334.
There are two devices on the sam WLAN. They use static IP addresses with Syncthing set to the default
The WLAN has both a 2.4 and 5 GHz networks set under the same name and password. One of the two devices switched from the 2.4 to the 5 GHz one about 45 minutes ago.
After that happened, Syncthing on the other device changed the device’s state to “Disconnected”. However, Syncthing on the first device, where the network switched to 5 GHz, still thinks that the two devices are connected.
Device 1 (no network change):
Device 2 is marked as “Disconnected”. 45+ minutes has passed, but the state is not changing.
These messages are repeated in the log:
2021-05-13 01:01:28 Failed to exchange Hello messages with 7LDIBZ4 at [::]:22000-10.0.0.3:22000/quic-client/TLS1.3-TLS_AES_128_GCM_SHA256: deadline exceeded
Device 2 (switched from 2.4 to 5 Ghz):
Device 1 still marked as “Connected”. The files are not syncing though.
This is the last relevant entry in the log:
2021-05-13 00:18:51 Established secure connection to D4DZUGP at 10.0.0.3:22000-10.0.0.2:22000/tcp-server/TLS1.3-TLS_CHACHA20_POLY1305_SHA256 2021-05-13 00:18:51 Replacing old connection 10.0.0.3:22000-10.0.0.2:22000/tcp-server/TLS1.3-TLS_CHACHA20_POLY1305_SHA256 with 10.0.0.3:22000-10.0.0.2:22000/tcp-server/TLS1.3-TLS_CHACHA20_POLY1305_SHA256 for D4DZUGP
I think that now that I know when this happens, I can probably reproduce the problem. Can something be done with this kind of a situation though? I can pause and unpause Device 1 on Device 2, which will force it to reconnect, but this is just a manual workaround…
Edit: The devices have finally reconnected for real after being stuck in that state for about 1 hour or so. This means that the problem does get fixed by itself eventually, although 1 hour seems a little excessive.