Fatal error: Uncaught Error: Call to undefined function stream_socket_server() in /users/energydata/www/volkszaehler.org/vendor/react/socket/src/TcpServer.php:170 Stack trace: #0 /users/energydata/www/volkszaehler.org/vendor/react/socket/src/Server.php(77): React\Socket\TcpServer->__construct('tcp://0.0.0.0:9...', Object(React\EventLoop\StreamSelectLoop), Array) #1 /users/energydata/www/volkszaehler.org/vendor/ratchet/rfc6455/tests/ab/startServer.php(15): React\Socket\Server->__construct('0.0.0.0:9001', Object(React\EventLoop\StreamSelectLoop)) #2 {main} thrown in /users/energydata/www/volkszaehler.org/vendor/react/socket/src/TcpServer.php on line 170