我正在尝试使用sqoop2将数据从oracle11g2服务器复制到hdfs。
到oracle的链接似乎有效，因为如果我使用无效的凭据，它会抱怨。定义如下：

link with id 14 and name OLink (Enabled: true, Created by xxx at 2/9/16 2:48 PM, Updated by xxx at 2/11/16 10:08 AM)
Using Connector generic-jdbc-connector with id 4
  Link configuration
    JDBC Driver Class: oracle.jdbc.driver.OracleDriver
    JDBC Connection String: jdbc:oracle:thin:@(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=localhost)(PORT=5999)))(CONNECT_DATA=(SERVER=DEDICATED)(SID=abc)))
    Username: xxx
    Password:
    JDBC Connection Properties:

（奇怪的端口号在这里，因为我现在需要使用反向隧道来访问数据库。很快就会修好）
作业定义如下

Job with id 2 and name Test OLink (Enabled: true, Created by xxx at 2/9/16 2:56 PM, Updated by xxx at 2/11/16 10:58 AM)
Using link id 14 and Connector id 4
  From database configuration
    Schema name: xxx
    Table name: t_name
    Table SQL statement:
    Table column names:
    Partition column name: CL_ID
    Null value allowed for the partition column: false
    Boundary query:
  Throttling resources
    Extractors: 3
    Loaders: 3
  ToJob configuration
    Override null value:
    Null value:
    Output format: TEXT_FILE
    Compression format: DEFAULT
    Custom compression format:
    Output directory: /tmp

当我启动作业（将verbose mode设置为true）时，它会列出远程表的所有列名和类型（意味着与oracle的连接正常），但是作业失败，例如

2016-02-11 10:44:42 UTC: BOOTING  - Progress is not available
2016-02-11 10:44:59 UTC: RUNNING  - 0.00 %
2016-02-11 10:45:09 UTC: RUNNING  - 0.00 %
2016-02-11 10:45:19 UTC: RUNNING  - 0.00 %
2016-02-11 10:45:29 UTC: FAILED
Exception: Job Failed with status:3
Stack trace: Task failed task_1450719316904_0239_m_000000
Job failed as tasks failed. failedMaps:1 failedReduces:0

日志显示如下：

2016-02-11 10:44:59,651 INFO [RMCommunicator Allocator] org.apache.hadoop.mapreduce.v2.app.rm.RMContainerRequestor: getResources() for application_1450719316904_0239: ask=1 release= 0 newContainers=0 finishedContainers=0 resourcelimit=<memory:56320, vCores:37> knownNMs=5
2016-02-11 10:45:04,775 INFO [Socket Reader #1 for port 54706] SecurityLogger.org.apache.hadoop.ipc.Server: Auth successful for job_1450719316904_0239 (auth:SIMPLE)
2016-02-11 10:45:04,803 INFO [IPC Server handler 5 on 54706] org.apache.hadoop.mapred.TaskAttemptListenerImpl: JVM with ID : jvm_1450719316904_0239_m_000002 asked for a task
2016-02-11 10:45:04,803 INFO [IPC Server handler 5 on 54706] org.apache.hadoop.mapred.TaskAttemptListenerImpl: JVM with ID: jvm_1450719316904_0239_m_000002 given task: attempt_1450719316904_0239_m_000000_0
2016-02-11 10:45:06,494 INFO [IPC Server handler 5 on 54706] org.apache.hadoop.mapred.TaskAttemptListenerImpl: Progress of TaskAttempt attempt_1450719316904_0239_m_000000_0 is : 0.0
2016-02-11 10:45:06,503 FATAL [IPC Server handler 6 on 54706] org.apache.hadoop.mapred.TaskAttemptListenerImpl: Task: attempt_1450719316904_0239_m_000000_0 - exited : org.apache.sqoop.common.SqoopException: MAPRED_EXEC_0017:Error occurs during extractor run
    at org.apache.sqoop.job.mr.SqoopMapper.run(SqoopMapper.java:99)
    at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:787)
    at org.apache.hadoop.mapred.MapTask.run(MapTask.java:341)
    at org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:163)
    at java.security.AccessController.doPrivileged(Native Method)
    at javax.security.auth.Subject.doAs(Subject.java:415)
    at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1671)
    at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:158)
Caused by: org.apache.sqoop.common.SqoopException: GENERIC_JDBC_CONNECTOR_0001:Unable to get a connection
    at org.apache.sqoop.connector.jdbc.GenericJdbcExecutor.<init>(GenericJdbcExecutor.java:59)
    at org.apache.sqoop.connector.jdbc.GenericJdbcExtractor.extract(GenericJdbcExtractor.java:50)
    at org.apache.sqoop.connector.jdbc.GenericJdbcExtractor.extract(GenericJdbcExtractor.java:38)
    at org.apache.sqoop.job.mr.SqoopMapper.run(SqoopMapper.java:95)
    ... 7 more
Caused by: java.sql.SQLRecoverableException: IO Error: The Network Adapter could not establish the connection
    at oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:489)
    at oracle.jdbc.driver.PhysicalConnection.<init>(PhysicalConnection.java:553)
    at oracle.jdbc.driver.T4CConnection.<init>(T4CConnection.java:254)
    at oracle.jdbc.driver.T4CDriverExtension.getConnection(T4CDriverExtension.java:32)
    at oracle.jdbc.driver.OracleDriver.connect(OracleDriver.java:528)
    at java.sql.DriverManager.getConnection(DriverManager.java:571)
    at java.sql.DriverManager.getConnection(DriverManager.java:215)
    at org.apache.sqoop.connector.jdbc.GenericJdbcExecutor.<init>(GenericJdbcExecutor.java:51)
    ... 10 more
Caused by: oracle.net.ns.NetException: The Network Adapter could not establish the connection
    at oracle.net.nt.ConnStrategy.execute(ConnStrategy.java:439)
    at oracle.net.resolver.AddrResolution.resolveAndExecute(AddrResolution.java:454)
    at oracle.net.ns.NSProtocol.establishConnection(NSProtocol.java:693)
    at oracle.net.ns.NSProtocol.connect(NSProtocol.java:251)
    at oracle.jdbc.driver.T4CConnection.connect(T4CConnection.java:1140)
    at oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:340)
    ... 17 more
Caused by: java.net.ConnectException: Connection refused
    at java.net.PlainSocketImpl.socketConnect(Native Method)
    at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:339)
    at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:200)
    at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:182)
    at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
    at java.net.Socket.connect(Socket.java:579)
    at oracle.net.nt.TcpNTAdapter.connect(TcpNTAdapter.java:149)
    at oracle.net.nt.ConnOption.connect(ConnOption.java:133)
    at oracle.net.nt.ConnStrategy.execute(ConnStrategy.java:405)
    ... 22 more

软件版本是
sqoop 1.99.5-cdh5.4.8源代码版本5d69aef6c630a68db47724e4541e02983ade3d67由jenkins于2015年10月15日星期四08:50:55 pdt编译
java版本“1.7.0\U 67”
java（tm）se运行时环境（build 1.7.0\u 67-b01）
java hotspot（tm）64位服务器虚拟机（内部版本24.65-b04，混合模式）
有没有关于如何解决这个问题的线索？