apache/hadoop · error · BadRequestException

Only 'KILLED' is allowed as a target state.

Error message

Only 'KILLED' is allowed as a target state.

What it means

The only state change the AM REST task-attempt endpoint implements is kill. If the requested state differs from the attempt's current state and is not KILLED, AMWebServices throws BadRequestException - HTTP 400 with "Only 'KILLED' is allowed as a target state.". A PUT whose target equals the current state succeeds as a no-op.

Source

Thrown at hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-app/src/main/java/org/apache/hadoop/mapreduce/v2/app/webapp/AMWebServices.java:487

    init();
    Job job = getJobFromJobIdString(jid, appCtx);
    checkAccess(job, hsr);

    String remoteUser = hsr.getRemoteUser();
    UserGroupInformation callerUGI = null;
    if (remoteUser != null) {
      callerUGI = UserGroupInformation.createRemoteUser(remoteUser);
    }

    Task task = getTaskFromTaskIdString(tid, job);
    TaskAttempt ta = getTaskAttemptFromTaskAttemptString(attId, task);
    if (!ta.getState().toString().equals(targetState.getState())) {
      // user is attempting to change state. right we only
      // allow users to kill the job task attempt
      if (targetState.getState().equals(TaskAttemptState.KILLED.toString())) {
        return killJobTaskAttempt(ta, callerUGI, hsr);
      }
      throw new BadRequestException("Only '"
          + TaskAttemptState.KILLED.toString()
          + "' is allowed as a target state.");
    }

    JobTaskAttemptState ret = new JobTaskAttemptState();
    ret.setState(ta.getState().toString());

    return Response.status(Status.OK).entity(ret).build();
  }

  @GET
  @Path("/jobs/{jobid}/tasks/{taskid}/attempts/{attemptid}/counters")
  @Produces({ MediaType.APPLICATION_JSON + "; " + JettyUtils.UTF_8,
      MediaType.APPLICATION_XML + "; " + JettyUtils.UTF_8 })
  public JobTaskAttemptCounterInfo getJobTaskAttemptIdCounters(
      @Context HttpServletRequest hsr, @PathParam("jobid") String jid,
      @PathParam("taskid") String tid, @PathParam("attemptid") String attId) {

View on GitHub (pinned to 2add963021)

Solutions

1. Send {"state":"KILLED"} - the only supported target
2. GET .../attempts/{attemptid} first and skip the PUT when the state already matches
3. For broader control use the job-level kill: PUT /ws/v1/mapreduce/jobs/{jobid}/state with {"state":"KILLED"}

Example fix

// before
PUT .../tasks/task_1_0001_m_000005/attempts/attempt_1_0001_m_000005_0/state
{ "state": "SUCCEEDED" }
// 400 { "Only 'KILLED' is allowed as a target state." }

// after
{ "state": "KILLED" }

if (!"KILLED".equals(requestedState)
    && !requestedState.equals(currentAttemptState)) {
  throw new IllegalArgumentException(
      "Only KILLED is a supported target state via the AM REST API");
}

static boolean isSupportedAttemptStateChange(String target, String current) {
  return target.equals(current) || "KILLED".equals(target);
}

try {
  return putAttemptState(jid, tid, attId, target);
} catch (javax.ws.rs.BadRequestException bre) {
  // only KILLED is allowed; surface to the caller instead of retrying other states
  throw new UnsupportedOperationException("attempt state changes limited to KILLED", bre);
}

When it happens

Trigger: PUT /ws/v1/mapreduce/jobs/{jobid}/tasks/{taskid}/attempts/{attemptid}/state with body {"state":"SUCCEEDED"} (or FAILED, RUNNING, ...) while the attempt is in a different state.

Common situations: Clients try to drive attempt lifecycle (rerun, force-fail, succeed) through the REST API; automation ported from MRv1 control interfaces assumes a full state machine that the API does not expose.

Understand the failure class

Background: "Invalid state transition" errors: "status must be X, actually Y", "already rejected/charging/uninstalled", "cannot ... while running" — what they mean when a library rejects your call — this error's family across 31 libraries.

Related errors

• tasktype must be either m or r
• startedTimeEnd must be greater than 0
• startedTimeEnd must be greater than startTimeBegin
• finishedTimeBegin must be greater than 0
• finishedTimeEnd must be greater than 0

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/2f07d7e19b5a5ad6. Report an issue: GitHub.