apache/hadoop · error · HadoopIllegalArgumentException

".snapshot" is a reserved name.

Error message

".snapshot" is a reserved name.

What it means

Error "".snapshot" is a reserved name." thrown in apache/hadoop.

Source

Thrown at hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSDirectory.java:1265

      if (q != null) { // a directory with quota
        try {
          q.verifyQuota(deltas);
        } catch (QuotaExceededException e) {
          e.setPathName(iip.getPath(i));
          throw e;
        }
      }
    }
  }

  /** Verify if the inode name is legal. */
  void verifyINodeName(byte[] childName) throws HadoopIllegalArgumentException {
    if (Arrays.equals(HdfsServerConstants.DOT_SNAPSHOT_DIR_BYTES, childName)) {
      String s = "\"" + HdfsConstants.DOT_SNAPSHOT_DIR + "\" is a reserved name.";
      if (!namesystem.isImageLoaded()) {
        s += "  Please rename it before upgrade.";
      }
      throw new HadoopIllegalArgumentException(s);
    }
  }

  /**
   * Verify child's name for fs limit.
   *
   * @param childName byte[] containing new child name
   * @param parentPath String containing parent path
   * @throws PathComponentTooLongException child's name is too long.
   */
  void verifyMaxComponentLength(byte[] childName, String parentPath)
      throws PathComponentTooLongException {
    if (maxComponentLength == 0) {
      return;
    }

    final int length = childName.length;
    if (length > maxComponentLength) {

View on GitHub (pinned to 2add963021)

Solutions

1. '.snapshot' is reserved for the snapshot mechanism; choose a different name for the file or directory.

When it happens

Trigger: Creating a file or directory named '.snapshot', which is reserved by HDFS for snapshot access.

Common situations: See trigger scenarios.

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/fd13bfae8df29b89. Report an issue: GitHub.