我正在使用hiveserver2进行连接，但是在配置单元中运行了几个作业之后，在配置单元日志中出现了以下错误。

2014-12-30 05:55:54,594 ERROR server.TThreadPoolServer (TThreadPoolServer.java:run(234)) - Error occurred during processing of message.
java.lang.RuntimeException: org.apache.thrift.transport.TTransportException
        at org.apache.thrift.transport.TSaslServerTransport$Factory.getTransport(TSaslServerTransport.java:219)
        at org.apache.thrift.server.TThreadPoolServer$WorkerProcess.run(TThreadPoolServer.java:209)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
        at java.lang.Thread.run(Thread.java:745)
Caused by: org.apache.thrift.transport.TTransportException
        at org.apache.thrift.transport.TIOStreamTransport.read(TIOStreamTransport.java:132)
        at org.apache.thrift.transport.TTransport.readAll(TTransport.java:84)
        at org.apache.thrift.transport.TSaslTransport.receiveSaslMessage(TSaslTransport.java:182)
        at org.apache.thrift.transport.TSaslServerTransport.handleSaslStartMessage(TSaslServerTransport.java:125)
        at org.apache.thrift.transport.TSaslTransport.open(TSaslTransport.java:253)
        at org.apache.thrift.transport.TSaslServerTransport.open(TSaslServerTransport.java:41)
        at org.apache.thrift.transport.TSaslServerTransport$Factory.getTransport(TSaslServerTransport.java:216)

在此之后，我无法连接到hiveserver2，重新启动hiveserver2服务后，我可以连接。
这个问题的根本原因是什么？
谢谢