RTDB connection failing repeatedly when connected on certain wifi networks

[Renan]

My app's RTDB fails to connect and keeps retrying indefinitely when connected to certain wifi networks.

Firebase Auth works normally under the same wifi, meaning the user can login and logoff normally, but any DB operation is only persisted locally and any OnCompletionListener hangs indefinitely and never completes (no errors or responses).

Offline persistence is enabled. /.info/connected returns false.

When I disconnect from the wifi and reconnect to the mobile network, the app works normally.

The same issue has been happening to several users (100+), although I can't say for sure it's also related to their wifi or some other underlying condition as I can't reliably reproduce this issue.

Today I finally got access to a testing device with the issue and was able to get some logs:

06-19 10:26:04.979 5921-6013 D: conn_31 - Opening a connection

06-19 10:26:34.982 5921-6013 D: ws_31 - timed out on connect

    ws_31 - closed

    ws_31 - closing itself

06-19 10:26:34.982 5921-6013 D: conn_31 - Realtime connection failed

06-19 10:26:34.983 5921-6013 D: conn_31 - closing realtime connection

06-19 10:26:34.983 5921-6013 D: pc_0 - Got on disconnect due to OTHER

    pc_0 - Scheduling connection attempt

06-19 10:26:34.983 5921-6013 D: Scheduling retry in 1174ms

06-19 10:26:36.158 5921-6013 D: pc_0 - Trying to fetch auth token

06-19 10:26:36.161 5921-6013 D: pc_0 - Successfully fetched token, opening connection

06-19 10:26:36.162 5921-6013 D: conn_32 - Opening a connection

06-19 10:27:06.164 5921-6013 D: ws_32 - timed out on connect

06-19 10:27:06.165 5921-6013 D: ws_32 - closed

    ws_32 - closing itself

06-19 10:27:06.165 5921-6013 D: conn_32 - Realtime connection failed

    conn_32 - closing realtime connection

06-19 10:27:06.165 5921-6013 D: pc_0 - Got on disconnect due to OTHER

    pc_0 - Scheduling connection attempt

06-19 10:27:06.166 5921-6013 D: Scheduling retry in 1189ms

06-19 10:27:07.355 5921-6013 D: pc_0 - Trying to fetch auth token

06-19 10:27:07.358 5921-6013 D: pc_0 - Successfully fetched token, opening connection

06-19 10:27:07.359 5921-6013 D: conn_33 - Opening a connection

06-19 10:27:37.361 5921-6013 D: ws_33 - timed out on connect

06-19 10:27:37.362 5921-6013 D: ws_33 - closed

    ws_33 - closing itself

06-19 10:27:37.362 5921-6013 D: conn_33 - Realtime connection failed

    conn_33 - closing realtime connection

06-19 10:27:37.362 5921-6013 D: pc_0 - Got on disconnect due to OTHER

06-19 10:27:37.364 5921-6013 D: pc_0 - Scheduling connection attempt

06-19 10:27:37.364 5921-6013 D: Scheduling retry in 2102ms

06-19 10:27:39.467 5921-6013 D: pc_0 - Trying to fetch auth token

06-19 10:27:39.469 5921-6013 D: pc_0 - Successfully fetched token, opening connection

06-19 10:27:39.470 5921-6013 D: conn_34 - Opening a connection

06-19 10:28:09.472 5921-6013 D: ws_34 - timed out on connect

    ws_34 - closed

    ws_34 - closing itself

06-19 10:28:09.473 5921-6013 D: conn_34 - Realtime connection failed

    conn_34 - closing realtime connection

06-19 10:28:09.473 5921-6013 D: pc_0 - Got on disconnect due to OTHER

    pc_0 - Scheduling connection attempt

06-19 10:28:09.473 5921-6013 D: Scheduling retry in 2360ms

06-19 10:28:11.834 5921-6013 D: pc_0 - Trying to fetch auth token

06-19 10:28:11.837 5921-6013 D: pc_0 - Successfully fetched token, opening connection

06-19 10:28:11.837 5921-6013 D: conn_35 - Opening a connection

06-19 10:28:41.840 5921-6013 D: ws_35 - timed out on connect

06-19 10:28:41.841 5921-6013 D: ws_35 - closed

    ws_35 - closing itself

06-19 10:28:41.841 5921-6013 D: conn_35 - Realtime connection failed

    conn_35 - closing realtime connection

06-19 10:28:41.841 5921-6013 D: pc_0 - Got on disconnect due to OTHER

06-19 10:28:41.842 5921-6013 D: pc_0 - Scheduling connection attempt

06-19 10:28:41.842 5921-6013 D: Scheduling retry in 2697ms

06-19 10:28:44.540 5921-6013 D: pc_0 - Trying to fetch auth token

06-19 10:28:44.544 5921-6013 D: pc_0 - Successfully fetched token, opening connection

06-19 10:28:44.546 5921-6013 D: conn_36 - Opening a connection

I have plenty of other logs, that I'm happy to share privately.

For now, I would love to hear any ideas that might help me properly reproduce and debug this issue.