With the latest 0.11.1.0-SNAPSHOT it happens that the Kafka Connect example using connect-console-sink/source.properties doesn't work anymore because the needed "file" property isn't found. This is because the underlying used FileStreamSink/Source connector and task has defined a ConfigDef with "file" as mandatory parameter. In the case of console example we want to have file=null so that stdin and stdout are used.
One possible solution and workaround is set "file=" inside the provided connect-console-sink/source.properties. The other one could be modify the FileStreamSink/Source source code in order to remove the "file" definition from the ConfigDef.