apache/hadoop · error · IOException

Could not launch job

Error message

Could not launch job

What it means

Error "Could not launch job" thrown in apache/hadoop.

Source

Thrown at hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/JobSubmitter.java:257

      // Set reservation info if it exists
      ReservationId reservationId = job.getReservationId();
      if (reservationId != null) {
        conf.set(MRJobConfig.RESERVATION_ID, reservationId.toString());
      }

      // Write job file to submit dir
      writeConf(conf, submitJobFile);
      
      //
      // Now, actually submit the job (using the submit name)
      //
      printTokens(jobId, job.getCredentials());
      status = submitClient.submitJob(
          jobId, submitJobDir.toString(), job.getCredentials());
      if (status != null) {
        return status;
      } else {
        throw new IOException("Could not launch job");
      }
    } finally {
      if (status == null) {
        LOG.info("Cleaning up the staging area " + submitJobDir);
        if (jtFs != null && submitJobDir != null)
          jtFs.delete(submitJobDir, true);

      }
    }
  }
  
  private void checkSpecs(Job job) throws ClassNotFoundException, 
      InterruptedException, IOException {
    JobConf jConf = (JobConf)job.getConfiguration();
    // Check the output specification
    if (jConf.getNumReduceTasks() == 0 ? 
        jConf.getUseNewMapper() : jConf.getUseNewReducer()) {
      org.apache.hadoop.mapreduce.OutputFormat<?, ?> output =

View on GitHub (pinned to 2add963021)

Solutions

  1. Examine the wrapped exception and cluster ResourceManager logs for the launch failure cause, fix it, and resubmit.

When it happens

Trigger: Thrown at hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/JobSubmitter.java:257 when the library encounters an invalid state.

Common situations: See trigger scenarios.


AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/01328a7619da7a76. Report an issue: GitHub.