{"record":{"id":"bd82504843b4853a","repo":"apache/hadoop","slug":"your-client-is-too-old-to-read-this-block-its-fo","errorCode":null,"errorMessage":"Your client is too old to read this block!  Its format version is {}, but the highest format version you can read is {}","messagePattern":"Your client is too old to read this block!  Its format version is (.+?), but the highest format version you can read is (.+?)","errorType":"exception","errorClass":"ShortCircuitFdsVersionException","httpStatus":null,"severity":"error","filePath":"hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/DataNode.java","lineNumber":2487,"sourceCode":"  @InterfaceAudience.LimitedPrivate(\"HDFS\")\n  static public class ShortCircuitFdsVersionException extends IOException {\n    private static final long serialVersionUID = 1L;\n    public ShortCircuitFdsVersionException(String msg) {\n      super(msg);\n    }\n  }\n\n  FileInputStream[] requestShortCircuitFdsForRead(final ExtendedBlock blk,\n      final Token<BlockTokenIdentifier> token, int maxVersion) \n          throws ShortCircuitFdsUnsupportedException,\n            ShortCircuitFdsVersionException, IOException {\n    if (fileDescriptorPassingDisabledReason != null) {\n      throw new ShortCircuitFdsUnsupportedException(\n          fileDescriptorPassingDisabledReason);\n    }\n    int blkVersion = CURRENT_BLOCK_FORMAT_VERSION;\n    if (maxVersion < blkVersion) {\n      throw new ShortCircuitFdsVersionException(\"Your client is too old \" +\n        \"to read this block!  Its format version is \" + \n        blkVersion + \", but the highest format version you can read is \" +\n        maxVersion);\n    }\n    metrics.incrBlocksGetLocalPathInfo();\n    FileInputStream fis[] = new FileInputStream[2];\n    \n    try {\n      checkStorageState(\"requestShortCircuitFdsForRead\");\n      fis[0] = (FileInputStream)data.getBlockInputStream(blk, 0);\n      fis[1] = DatanodeUtil.getMetaDataInputStream(blk, data);\n    } catch (ClassCastException e) {\n      LOG.debug(\"requestShortCircuitFdsForRead failed\", e);\n      throw new ShortCircuitFdsUnsupportedException(\"This DataNode's \" +\n          \"FsDatasetSpi does not support short-circuit local reads\");\n    }\n    return fis;\n  }","sourceCodeStart":2469,"sourceCodeEnd":2505,"githubUrl":"https://github.com/apache/hadoop/blob/2add9630210752f88ceb1bb74eb65e37bf41da8e/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/DataNode.java#L2469-L2505","documentation":"Error \"Your client is too old to read this block!  Its format version is {}, but the highest format version you can read is {}\" thrown in apache/hadoop.","triggerScenarios":"A client using an older metadata format version attempts a short-circuit read of a block whose on-disk meta file uses a newer format.","commonSituations":"The client library is older than the block's on-disk format version. Upgrade the client to a version supporting the cluster's layout version.","solutions":["Upgrade the client to a Hadoop version whose meta format version supports the block metadata version on disk.","Or downgrade/rewrite the block metadata to a version the client supports (not typical; upgrading the client is preferred)."],"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"}