我对kafka还很陌生，我正在尝试用一个mysql源连接器和一个elasticsearch+elasticsearch sink连接器建立一个简单的kafka连接系统并运行；用于基本数据流目的。
我是按照https://www.confluent.io/blog/simplest-useful-kafka-connect-data-pipeline-world-thereabouts-part-1/ &它的第2部分（我已经验证了es的工作原理是在源代码端有一个简单的生产者。）
除了mysql源连接器之外，其他一切都按预期配置和工作。我尝试这一切的虚拟机上没有安装mysql服务器。教程的dbms部分我使用客户机来创建/更改和处理表。因此，在源属性中，我尝试：

"connection.url": "jdbc:mysql://IPaddressofDB:3306/DBname?user=uname&password=pwd"
"table.whitelist": "tablename"

为了启动连接器，我只做了一个 ./confluent load connector-name 当我加载源连接器并检查其状态时，它会给出一个错误

"org.apache.kafka.connect.errors.ConnectException: Failed trying to validate that columns used for offsets are NOT NULL\n\t ...
 Caused by: java.sql.SQLSyntaxErrorException: Table 'admin_portal.tablename' doesn't exist\n\t

这是对的吗？我完全错过了什么吗？
如何为我正在尝试的情况指定connection.url：您正在尝试连接到不同的db服务器？几乎所有的例子/git问题等似乎都只指定localhost。
我不知道在哪里 admin_portal 是从哪里来的，我根本没说

****为@robin moffat的建议编辑（似乎给出了与以前相同的错误）

sourceconfig.json文件：

{
        "name": "jdbc_source_mysql_new",
        "config": {
                "connector.class": "io.confluent.connect.jdbc.JdbcSourceConnector",
                "connection.url": "jdbc:mysql://ipaddress:3306/dbname?user=uname&password=pwd",
                "table.whitelist": "dbname.tablename",
                "topic.prefix": "mysql-new-",
                "mode":"incrementing",
                "incrementing.column.name": "colname"
                }
}

已加载连接器：

>curl -X POST -H "Content-Type: application/json" --data @sourceconfig.json http://localhost:8083/connectors

检查接头的状态：

>curl -X GET localhost:8083/connectors/jdbc_source_mysql_new/tasks/0/status

  {"state":"FAILED","
     "trace": 
     "org.apache.kafka.connect.errors.ConnectException: Failed trying to validate that columns used for offsets are NOT NULL\n\t
     at io.confluent.connect.jdbc.source.JdbcSourceTask.validateNonNullable(JdbcSourceTask.java:400)\n\t
     at io.confluent.connect.jdbc.source.JdbcSourceTask.start(JdbcSourceTask.java:156)\n\t
     at org.apache.kafka.connect.runtime.WorkerSourceTask.execute(WorkerSourceTask.java:198)\n\t
     at org.apache.kafka.connect.runtime.WorkerTask.doRun(WorkerTask.java:175)\n\t
     at org.apache.kafka.connect.runtime.WorkerTask.run(WorkerTask.java:219)\n\t
     at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)\n\t
     at java.util.concurrent.FutureTask.run(FutureTask.java:266)\n\t
     at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)\n\t
     at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)\n\t
 at java.lang.Thread.run(Thread.java:748)\n

 Caused by: java.sql.SQLSyntaxErrorException: Table 'admin_portal.tablename' doesn't exist\n\t
 at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:120)\n\t
 at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:97)\n\t
 at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:122)\n\t
 at com.mysql.cj.jdbc.StatementImpl.executeQuery(StatementImpl.java:1218)\n\t
 at com.mysql.cj.jdbc.DatabaseMetaData$7.forEach(DatabaseMetaData.java:2950)\n\t
 at com.mysql.cj.jdbc.DatabaseMetaData$7.forEach(DatabaseMetaData.java:2938)\n\t
 at com.mysql.cj.jdbc.IterateBlock.doForAll(IterateBlock.java:56)\n\t
 at com.mysql.cj.jdbc.DatabaseMetaData.getPrimaryKeys(DatabaseMetaData.java:2991)\n\t
 at io.confluent.connect.jdbc.dialect.GenericDatabaseDialect.primaryKeyColumns(GenericDatabaseDialect.java:696)\n\t
 at io.confluent.connect.jdbc.dialect.GenericDatabaseDialect.describeColumns(GenericDatabaseDialect.java:533)\n\t
 at io.confluent.connect.jdbc.dialect.GenericDatabaseDialect.describeColumns(GenericDatabaseDialect.java:513)\n\t
 at io.confluent.connect.jdbc.source.JdbcSourceTask.validateNonNullable(JdbcSourceTask.java:369)\n\t... 9 more\n",}