apache/hadoop · error · RuntimeException

Invalid entry! Missing hostname

Error message

Invalid entry! Missing hostname

What it means

Error "Invalid entry! Missing hostname" thrown in apache/hadoop.

Source

Thrown at hadoop-tools/hadoop-rumen/src/main/java/org/apache/hadoop/tools/rumen/LoggedTaskAttempt.java:348

  void setFinishTime(long finishTime) {
    this.finishTime = finishTime;
  }

  public NodeName getHostName() {
    return hostName;
  }

  // This is needed for JSON deserialization
  void setHostName(String hostName) {
    this.hostName = hostName == null ? null : new NodeName(hostName);
  }

  // In job-history, hostName is saved in the format rackName/NodeName
  //TODO this is a hack! The '/' handling needs fixing.
  void setHostName(String hostName, String rackName) {
    if (hostName == null || hostName.length() == 0) {
      throw new RuntimeException("Invalid entry! Missing hostname");
    } else if (rackName == null || rackName.length() == 0) {
      setHostName(hostName);
    } else {
      // make sure that the rackname is prefixed with a '/'
      if (!rackName.startsWith("/")) {
        rackName = "/" + rackName;
      }
      // make sure that the hostname is prefixed with a '/'
      if (!hostName.startsWith("/")) {
        hostName = "/" + hostName;
      }
      setHostName(rackName.intern() + hostName.intern());
    }
  }

  public long getHdfsBytesRead() {
    return hdfsBytesRead;
  }

View on GitHub (pinned to 2add963021)

Solutions

1. Check the job history log entry; the task attempt record is missing its hostname field.

When it happens

Trigger: A parsed job-history task attempt entry lacks the hostname field, so the attempt cannot be attributed to a node.

Common situations: See trigger scenarios.

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/769665d355f9b0b0. Report an issue: GitHub.