{"record":{"id":"59061fea571e39d6","repo":"apache/hadoop","slug":"invalid-node","errorCode":"INVALID_NODE","errorMessage":"The number of input nodes is 0. Please input the valid nodes.","messagePattern":"The number of input nodes is 0\\. Please input the valid nodes\\.","errorType":"validation","errorClass":"DiskBalancerException","httpStatus":null,"severity":"error","filePath":"hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/diskbalancer/command/Command.java","lineNumber":292,"sourceCode":"      listURL = new URL(listArg);\n      try {\n        HostsFileReader.readFileToSet(\"include\",\n            Paths.get(listURL.getPath()).toString(), resultSet);\n      } catch (NoSuchFileException e) {\n        String warnMsg = String\n            .format(\"The input host file path '%s' is not a valid path. \"\n                + \"Please make sure the host file exists.\", listArg);\n        throw new DiskBalancerException(warnMsg,\n            DiskBalancerException.Result.INVALID_HOST_FILE_PATH);\n      }\n    } else {\n      nodeData = listArg;\n      String[] nodes = nodeData.split(\",\");\n\n      if (nodes.length == 0) {\n        String warnMsg = \"The number of input nodes is 0. \"\n            + \"Please input the valid nodes.\";\n        throw new DiskBalancerException(warnMsg,\n            DiskBalancerException.Result.INVALID_NODE);\n      }\n\n      Collections.addAll(resultSet, nodes);\n    }\n\n    return resultSet;\n  }\n\n  /**\n   * Returns a DiskBalancer Node list from the Cluster or null if not found.\n   *\n   * @param listArg String File URL or a comma separated list of node names.\n   * @return List of DiskBalancer Node\n   * @throws IOException\n   */\n  protected List<DiskBalancerDataNode> getNodes(String listArg)\n      throws IOException {","sourceCodeStart":274,"sourceCodeEnd":310,"githubUrl":"https://github.com/apache/hadoop/blob/2add9630210752f88ceb1bb74eb65e37bf41da8e/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/diskbalancer/command/Command.java#L274-L310","documentation":"Error \"The number of input nodes is 0. Please input the valid nodes.\" thrown in apache/hadoop.","triggerScenarios":"DiskBalancer command when the parsed set of target nodes is empty, e.g. empty host file or no matching nodes.","commonSituations":"See trigger scenarios.","solutions":["Provide at least one valid DataNode hostname in the input nodes list or host file.","Check the host file content for empty lines or formatting errors."],"exampleFix":null,"handlingStrategy":null,"validationCode":null,"typeGuard":null,"tryCatchPattern":null,"preventionTips":[],"tags":[],"backgroundTag":null,"analyzedSha":"2add9630210752f88ceb1bb74eb65e37bf41da8e","analyzedAt":"2026-08-22T19:55:07.957Z","schemaVersion":2},"datasetVersion":"2026-08-22T20:17:22.307Z"}