Troubleshooting failed jobs

You can identify and troubleshoot incomplete jobs on your cluster using Cloudera Observability On-Premises.

Describes how to locate and troubleshoot jobs that have failed to complete.

Steps with examples from a Virtual Cluster's Spark engine are used to describe how to further investigate and troubleshoot the root cause of a job that failed to finish.

  1. Verify that you are logged in to the Cloudera Observability On-Premises web UI.
    1. In the URL field of a supported web browser, enter the Cloudera Observability On-Premises URL that you were given by your system administrator and press Enter.
    2. When the Cloudera Observability On-Premises Log in page opens, enter your Cloudera Observability On-Premises user name and password access credentials.
    3. Click Log in.
      The Cloudera Observability On-Premises landing page opens.
  2. From the Environment Name column in the Environments page, locate and click the name of the environment whose workload diagnostic information requires analysis and troubleshooting.
    For this example, select Virtual Cluster from the Environments list and then select a Virtual Cluster required for analysis.

    The Environment navigation panel opens, which hierarchically lists the environment and its services hosted on the selected environment.

  3. Verify that the Cluster Summary page is displayed.

    The Cluster Summary page, displays performance trends and metrics about the cluster's processed jobs and queries.

  4. Optional: From the time-range list, select a time period that meets your requirements.
  5. In the Cluster Summary page, locate the Spark Jobs Trend chart widget and then click its Failed/Killed Jobs value.
    The engine's Jobs page opens.
  6. From the Health Check filter's list, select Failed to Finish, which filters the list to display a list of jobs that did not complete.
  7. To view more details about why a job failed to complete, from the Job column select a job's name. The job's page opens displaying information about the job you selected and where the failure happened.

  8. From the Failures section in the Diagnostic Information column, click More.
    The Diagnostic Information dialog box opens, which describes more details about why the job aborted. In the following example, the job was aborted whilst writing rows due to an out of bounds java exception:

  9. Click Close.
  10. To display more information about the stage where the job failed, in this case the Stage-2 process, in the Failing from column, click the stage's link. Or select the Execution Details tab and then click the failed stage's link.
    In the following example's Summary panel, it shows that Task 0 was attempted 4 times:

  11. To display more information about all the failed attempts, in the Summary panel, click the Failed task value.
    In the following example, the job aborted when Task 0 was writing rows. To understand more about what triggered the SparkException error message and to further troubleshoot the root cause, you can open the associated log file by clicking Full error log.