apache/hadoop · error · IOException

Source {} and destination {} must both be directories

Error message

Source {} and destination {} must both be directories

What it means

Error "Source {} and destination {} must both be directories" thrown in apache/hadoop.

Source

Thrown at hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSDirRenameOp.java:577

    }

    if (FSDirectory.isExactReservedName(src)
        || FSDirectory.isExactReservedName(dst)) {
      error = "Cannot rename to or from /.reserved";
      throw new InvalidPathException(error);
    }
  }

  private static void validateOverwrite(
      String src, String dst, boolean overwrite, INode srcInode, INode dstInode)
      throws IOException {
    String error;// It's OK to rename a file to a symlink and vice versa
    if (dstInode.isDirectory() != srcInode.isDirectory()) {
      error = "Source " + src + " and destination " + dst
          + " must both be directories";
      NameNode.stateChangeLog.warn("DIR* FSDirectory.unprotectedRenameTo: "
          + error);
      throw new IOException(error);
    }
    if (!overwrite) { // If destination exists, overwrite flag must be true
      error = "rename destination " + dst + " already exists";
      NameNode.stateChangeLog.warn("DIR* FSDirectory.unprotectedRenameTo: "
          + error);
      throw new FileAlreadyExistsException(error);
    }
    if (dstInode.isDirectory()) {
      final ReadOnlyList<INode> children = dstInode.asDirectory()
          .getChildrenList(Snapshot.CURRENT_STATE_ID);
      if (!children.isEmpty()) {
        error = "rename destination directory is not empty: " + dst;
        NameNode.stateChangeLog.warn("DIR* FSDirectory.unprotectedRenameTo: "
            + error);
        throw new IOException(error);
      }
    }
  }

View on GitHub (pinned to 2add963021)

Solutions

1. When renaming with snapshot diff restrictions, ensure both source and destination are directories.
2. Rename the directory instead of mixing a file with a directory path.

When it happens

Trigger: Renaming with the OVERWRITE/TO_TRASH options where either the source or the destination is not a directory while both must be directories.

Common situations: See trigger scenarios.

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/bcff9a96006f57fa. Report an issue: GitHub.