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
- 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.