apache/hadoop · error · IOException

rename source cannot be the root

Error message

rename source cannot be the root

What it means

Error "rename source cannot be the root" thrown in apache/hadoop.

Source

Thrown at hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSDirRenameOp.java:613

  }

  private static void validateRenameSource(FSDirectory fsd,
      INodesInPath srcIIP, List<INodeDirectory> snapshottableDirs)
      throws IOException {
    String error;
    final INode srcInode = srcIIP.getLastINode();
    // validate source
    if (srcInode == null) {
      error = "rename source " + srcIIP.getPath() + " is not found.";
      NameNode.stateChangeLog.warn("DIR* FSDirectory.unprotectedRenameTo: "
          + error);
      throw new FileNotFoundException(error);
    }
    if (srcIIP.length() == 1) {
      error = "rename source cannot be the root";
      NameNode.stateChangeLog.warn("DIR* FSDirectory.unprotectedRenameTo: "
          + error);
      throw new IOException(error);
    }
    // srcInode and its subtree cannot contain snapshottable directories with
    // snapshots
    FSDirSnapshotOp.checkSnapshot(fsd, srcIIP, snapshottableDirs);
  }

  private static void validateNestSnapshot(FSDirectory fsd, String srcPath,
      INodeDirectory dstParent, List<INodeDirectory> snapshottableDirs)
      throws SnapshotException {

    if (fsd.getFSNamesystem().getSnapshotManager().isAllowNestedSnapshots()) {
      return;
    }

    /*
     * snapshottableDirs is a list of snapshottable directory (child of rename
     * src) which do not have snapshots yet. If this list is not empty, that
     * means rename src has snapshottable descendant directories.

View on GitHub (pinned to 2add963021)

Solutions

1. The root directory cannot be renamed; select a subdirectory as the source.

When it happens

Trigger: Attempting to rename the filesystem root ('/').

Common situations: See trigger scenarios.

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/6f89ec0802ee11f5. Report an issue: GitHub.