apache/hadoop · error · IOException

Another DiskBalancer files already exist at the target locat

Error message

Another DiskBalancer files already exist at the target location. {path}

What it means

Error "Another DiskBalancer files already exist at the target location. {path}" thrown in apache/hadoop.

Source

Thrown at hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/diskbalancer/command/Command.java:199

    Date now = new Date();

    fs = FileSystem.get(getClusterURI(), getConf());
    if (path == null || path.isEmpty()) {
      if (getClusterURI().getScheme().startsWith("file")) {
        diskBalancerLogs = new Path(
            System.getProperty("user.dir") + DEFAULT_LOG_DIR.toString() +
                Path.SEPARATOR + format.format(now));
      } else {
        diskBalancerLogs = new Path(DEFAULT_LOG_DIR.toString() +
            Path.SEPARATOR + format.format(now));
      }
    } else {
      diskBalancerLogs = new Path(path);
    }
    if (fs.exists(diskBalancerLogs)) {
      LOG.debug("Another Diskbalancer instance is running ? - Target " +
          "Directory already exists. {}", diskBalancerLogs);
      throw new IOException("Another DiskBalancer files already exist at the " +
          "target location. " + diskBalancerLogs.toString());
    }
    fs.mkdirs(diskBalancerLogs);
  }

  /**
   * Sets the nodes to process.
   *
   * @param node - Node
   */
  protected void setNodesToProcess(DiskBalancerDataNode node) {
    List<DiskBalancerDataNode> nodelist = new LinkedList<>();
    nodelist.add(node);
    setNodesToProcess(nodelist);
  }

  /**
   * Sets the list of Nodes to process.

View on GitHub (pinned to 2add963021)

Solutions

1. Remove or move the existing DiskBalancer plan file at the target location before writing a new one.
2. Choose a different output path for the new plan file.

When it happens

Trigger: DiskBalancer plan submission when a plan file already exists at the target before/after location, indicating an unexecuted prior plan.

Common situations: See trigger scenarios.

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/db57c9c980e89830. Report an issue: GitHub.