Issues with VPN, connection not possible

[M-Stenzel]

Hi community,

I am using the latest version of owntracks for Android (latest version).
I use it with MQTT, no websockets option.
MQTT server is mosquitto (latest version), it listens on 0.0.0.0:8883.

Sometimes there are no updates of location, why?

Scenario 1: When the VPN is activated, owntracks app wants to connect with its WAN IP address.

2024-11-03 01:10:02.494 I [DefaultDispatcher-worker-1] MQTTReconnectWorker: MQTT reconnect worker job completed, status Retry
2024-11-03 01:10:22.546 I [DefaultDispatcher-worker-1] MQTTReconnectWorker: MQTT reconnect worker job started
2024-11-03 01:10:22.576 I [DefaultDispatcher-worker-1] MQTTMessageProcessorEndpoint$connectToBroker: Connecting to tcp://10.4.0.2:8883?# timeout = 30s
2024-11-03 01:10:52.616 E [DefaultDispatcher-worker-1] MQTTMessageProcessorEndpoint$connectToBroker: MQTT client unable to connect to endpoint
MqttException (0) - java.net.SocketTimeoutException: failed to connect to /10.4.0.2 (port 8883) from /172.16.252.1 (port 46168) after 30000ms
	at androidx.work.impl.utils.WorkForegroundUpdater$1.run(SourceFile:315)
	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:463)
	at java.util.concurrent.FutureTask.run(FutureTask.java:264)
	at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:307)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1137)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:637)
	at java.lang.Thread.run(Thread.java:1012)
Caused by: java.net.SocketTimeoutException: **failed to connect to /10.4.0.2 (port 8883) from /100.36.25.1 (port 46168)** after 30000ms
	at libcore.io.IoBridge.connectErrno(IoBridge.java:235)
	at libcore.io.IoBridge.connect(IoBridge.java:179)
	at java.net.PlainSocketImpl.socketConnect(PlainSocketImpl.java:142)
	at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:390)
	at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:230)
	at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:212)
	at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:436)
	at java.net.Socket.connect(Socket.java:646)
	at org.eclipse.paho.client.mqttv3.internal.TCPNetworkModule.start(Unknown Source:57)
	at androidx.work.impl.utils.WorkForegroundUpdater$1.run(SourceFile:75)
	... 6 more

Scenario 2: When the VPN is not activated, owntracks wants to connect with the VPN address.

2024-11-03 16:28:48.198 I [DefaultDispatcher-worker-5] MQTTReconnectWorker: MQTT reconnect worker job started
2024-11-03 16:28:48.221 I [DefaultDispatcher-worker-5] MQTTMessageProcessorEndpoint$connectToBroker: Connecting to tcp://65.109.156.85:8883?# timeout = 30s
2024-11-03 16:29:18.263 E [DefaultDispatcher-worker-5] MQTTMessageProcessorEndpoint$connectToBroker: MQTT client unable to connect to endpoint
MqttException (0) - java.net.SocketTimeoutException: failed to connect to /65.109.156.85 (port 8883) from /10.12.0.2 (port 44770) after 30000ms
	at androidx.work.impl.utils.WorkForegroundUpdater$1.run(SourceFile:315)
	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:463)
	at java.util.concurrent.FutureTask.run(FutureTask.java:264)
	at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:307)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1137)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:637)
	at java.lang.Thread.run(Thread.java:1012)
Caused by: java.net.SocketTimeoutException: **failed to connect to /35.154.15.22 (port 8883) from /10.12.0.2 (port 44770)** after 30000ms
	at libcore.io.IoBridge.connectErrno(IoBridge.java:235)
	at libcore.io.IoBridge.connect(IoBridge.java:179)
	at java.net.PlainSocketImpl.socketConnect(PlainSocketImpl.java:142)
	at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:390)
	at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:230)
	at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:212)
	at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:436)
	at java.net.Socket.connect(Socket.java:646)
	at org.eclipse.paho.client.mqttv3.internal.TCPNetworkModule.start(Unknown Source:57)
	at androidx.work.impl.utils.WorkForegroundUpdater$1.run(SourceFile:75)
	... 6 more

Both scenarios will obviously fail.

In the owntracks app I can enter only one endpoint host address.
There is the alternative of putting in the FQDN of the mosquitto server, but this does not help (will resolve to the WAN address).

Any ideas how to overcome the problem?