Random error with MySQL Plugin

Hi,

we've experienced lately random error with kitchen and MySQL plugi on ubuntu.
It seems like the plugin is not valid. Has anyone experienced the same issue?
This error occurs completely randomly, most of the time kitchen is working just fine.

The plugin being used is
data-integration/plugins/databases/pdi-mysql-plugin/lib/mysql-connector-java-5.1.23.jar


See log attached.


Thanks a lot


2015/10/10 03:31:14 - loadMySql - Dispatching started for transformation [loadMySql]
2015/10/10 03:31:14 - table_input.0 - ERROR (version 5.4.0.1-130, build 1 from 2015-06-14_12-34-55 by buildguy) : An error occurred, processing will be stopped:
2015/10/10 03:31:14 - table_input.0 - Error occurred while trying to connect to the database
2015/10/10 03:31:14 - table_input.0 -
2015/10/10 03:31:14 - table_input.0 - Exception while loading class
2015/10/10 03:31:14 - table_input.0 -
2015/10/10 03:31:14 - table_input.0 - Not a valid plugin
2015/10/10 03:31:14 - loadMySql - ERROR (version 5.4.0.1-130, build 1 from 2015-06-14_12-34-55 by buildguy) : Something went wrong while trying to stop the transformation: org.pentaho.di.core.exception.KettleDatabaseException:
2015/10/10 03:31:14 - loadMySql - Unable to get database metadata from this database connection
2015/10/10 03:31:14 - loadMySql - at java.lang.Thread.run (Thread.java:745)
2015/10/10 03:31:14 - loadMySql - at org.pentaho.di.trans.step.StepInitThread.run (StepInitThread.java:69)
2015/10/10 03:31:14 - loadMySql - at org.pentaho.di.trans.steps.tableinput.TableInput.init (TableInput.java:344)
2015/10/10 03:31:14 - loadMySql - at org.pentaho.di.trans.step.BaseStep.stopAll (BaseStep.java:2863)
2015/10/10 03:31:14 - loadMySql - at org.pentaho.di.trans.Trans.stopAll (Trans.java:1892)
2015/10/10 03:31:14 - loadMySql - at org.pentaho.di.trans.steps.tableinput.TableInput.stopRunning (TableInput.java:287)
2015/10/10 03:31:14 - loadMySql - at org.pentaho.di.core.database.Database.cancelQuery (Database.java:691)
2015/10/10 03:31:14 - loadMySql - at org.pentaho.di.core.database.Database.getDatabaseMetaData (Database.java:2758)
2015/10/10 03:31:14 - loadMySql - ERROR (version 5.4.0.1-130, build 1 from 2015-06-14_12-34-55 by buildguy) : org.pentaho.di.core.exception.KettleDatabaseException:
2015/10/10 03:31:14 - loadMySql - Unable to get database metadata from this database connection
2015/10/10 03:31:14 - loadMySql - at java.lang.Thread.run (Thread.java:745)
2015/10/10 03:31:14 - loadMySql - at org.pentaho.di.trans.step.StepInitThread.run (StepInitThread.java:69)
2015/10/10 03:31:14 - loadMySql - at org.pentaho.di.trans.steps.tableinput.TableInput.init (TableInput.java:344)
2015/10/10 03:31:14 - loadMySql - at org.pentaho.di.trans.step.BaseStep.stopAll (BaseStep.java:2863)
2015/10/10 03:31:14 - loadMySql - at org.pentaho.di.trans.Trans.stopAll (Trans.java:1892)
2015/10/10 03:31:14 - loadMySql - at org.pentaho.di.trans.steps.tableinput.TableInput.stopRunning (TableInput.java:287)
2015/10/10 03:31:14 - loadMySql - at org.pentaho.di.core.database.Database.cancelQuery (Database.java:691)
2015/10/10 03:31:14 - loadMySql - at org.pentaho.di.core.database.Database.getDatabaseMetaData (Database.java:2758)
2015/10/10 03:31:14 - loadMySql -
2015/10/10 03:31:14 - loadMySql - at org.pentaho.di.core.database.Database.getDatabaseMetaData(Database.java:2760)
2015/10/10 03:31:14 - loadMySql - at org.pentaho.di.core.database.Database.cancelQuery(Database.java:691)
2015/10/10 03:31:14 - loadMySql - at org.pentaho.di.trans.steps.tableinput.TableInput.stopRunning(TableInput.java:287)
2015/10/10 03:31:14 - loadMySql - at org.pentaho.di.trans.Trans.stopAll(Trans.java:1892)
2015/10/10 03:31:14 - loadMySql - at org.pentaho.di.trans.step.BaseStep.stopAll(BaseStep.java:2863)
2015/10/10 03:31:14 - loadMySql - at org.pentaho.di.trans.steps.tableinput.TableInput.init(TableInput.java:344)
2015/10/10 03:31:14 - loadMySql - at org.pentaho.di.trans.step.StepInitThread.run(StepInitThread.java:69)
2015/10/10 03:31:14 - loadMySql - at java.lang.Thread.run(Thread.java:745)
2015/10/10 03:31:14 - loadMySql - Caused by: java.lang.NullPointerException
2015/10/10 03:31:14 - loadMySql - at org.pentaho.di.core.database.Database.getDatabaseMetaData(Database.java:2758)
2015/10/10 03:31:14 - loadMySql - ... 7 more
2015/10/10 03:31:14 - table_input.0 - ERROR (version 5.4.0.1-130, build 1 from 2015-06-14_12-34-55 by buildguy) : Error initializing step [table_input]
2015/10/10 03:31:14 - loadMySql - ERROR (version 5.4.0.1-130, build 1 from 2015-06-14_12-34-55 by buildguy) : Step [table_input.0] failed to initialize!
2015/10/10 03:31:14 - table_input.0 - Finished reading query, closing connection.
2015/10/10 03:31:14 - loadMySql - ERROR (version 5.4.0.1-130, build 1 from 2015-06-14_12-34-55 by buildguy) : Unable to prepare for execution of the transformation
2015/10/10 03:31:14 - loadMySql - ERROR (version 5.4.0.1-130, build 1 from 2015-06-14_12-34-55 by buildguy) : org.pentaho.di.core.exception.KettleException:
2015/10/10 03:31:14 - loadMySql - We failed to initialize at least one step. Execution can not begin!
2015/10/10 03:31:14 - loadMySql -
2015/10/10 03:31:14 - loadMySql -
2015/10/10 03:31:14 - loadMySql - at org.pentaho.di.trans.Trans.prepareExecution(Trans.java:1149)
2015/10/10 03:31:14 - loadMySql - at org.pentaho.di.trans.Trans.execute(Trans.java:607)
2015/10/10 03:31:14 - loadMySql - at org.pentaho.di.job.entries.trans.JobEntryTrans.execute(JobEntryTrans.java:1065)
2015/10/10 03:31:14 - loadMySql - at org.pentaho.di.job.Job.execute(Job.java:716)
2015/10/10 03:31:14 - loadMySql - at org.pentaho.di.job.Job.execute(Job.java:859)
2015/10/10 03:31:14 - loadMySql - at org.pentaho.di.job.Job.execute(Job.java:598)
2015/10/10 03:31:14 - loadMySql - at org.pentaho.di.job.entries.job.JobEntryJobRunner.run(JobEntryJobRunner.java:69)
2015/10/10 03:31:14 - loadMySql - at java.lang.Thread.run(Thread.java:745)