I have two environments (DEV and PROD). Both are Linux running Connman as network manager. In my DEV environment the signal configurationAdded is working properly when I plug/unplug ethernet cable. On the other hand, in PROD env, with computer with the same hardware specifications, this signal is not emitted. My question in this topic is: which it is based Qt, in particular QtNetwork, to emit this signal? What their dependencies? I am assuming that I have any missing dependencies in PROD env by which this is not working properly.
I have read this QNetworkConfigurationManager::configurationChanged signal not getting called for ETHERNET config changes but in this question the user is asking for Windows, not for Linux. In any case it was not resolved.
EDIT: Checking QNetworkConfigurationManager::capabilities, the result in DEV environment is QFlags(0x1|0x10|0x20|0x40) while in PROD env is QFlags() (empty). So this can be a problem with QtNetwork backend in PROD env.
The issue is that app binary not getting right plugins path. In this case, the plugin needed is bearer. You can check this debugging with QLibraryInfo::location(QLibraryInfo::PluginsPath). If your path is not right, you can solve it using qt.conf file or setting paths. Both methods are specified in this Qt documentation article