apache/hadoop · error · IOException

Har: copyfromlocalfile not allowed

Error message

Har: copyfromlocalfile not allowed

What it means

The single-source copyFromLocalFile(boolean, boolean, Path, Path) override throws 'Har: copyfromlocalfile not allowed': uploading into a har would create new content, which the immutable archive forbids. Reads out of a har are supported (copyToLocalFile works), but writes in are not.

Source

Thrown at hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/HarFileSystem.java:833

  public void setWorkingDirectory(Path newDir) {
    //does nothing.
  }
  
  /**
   * not implemented.
   */
  @Override
  public boolean mkdirs(Path f, FsPermission permission) throws IOException {
    throw new IOException("Har: mkdirs not allowed");
  }
  
  /**
   * not implemented.
   */
  @Override
  public void copyFromLocalFile(boolean delSrc, boolean overwrite,
      Path src, Path dst) throws IOException {
    throw new IOException("Har: copyfromlocalfile not allowed");
  }

  @Override
  public void copyFromLocalFile(boolean delSrc, boolean overwrite,
      Path[] srcs, Path dst) throws IOException {
    throw new IOException("Har: copyfromlocalfile not allowed");
  }

  /**
   * copies the file in the har filesystem to a local file.
   */
  @Override
  public void copyToLocalFile(boolean delSrc, Path src, Path dst) 
    throws IOException {
    FileUtil.copy(this, src, getLocal(getConf()), dst, false, getConf());
  }
  
  /**

View on GitHub (pinned to 2add963021)

Solutions

1. Upload to the underlying HDFS first (fs.copyFromLocalFile(..., hdfsDst)), then rebuild or create the archive with `hadoop archive`
2. Update the script configuration so upload targets never use the har scheme
3. For one-off additions: copy the archive's source tree, add the file, re-run `hadoop archive`

Example fix

// before
fs.copyFromLocalFile(false, false, new Path("/tmp/f.dat"), new Path("har://hdfs-nn:8020/a/data.har/f.dat"));

// after
hdfs.copyFromLocalFile(false, false, new Path("/tmp/f.dat"), new Path("/a/data/f.dat"));
// then: hadoop archive -archiveName data.har -p /a/data /a

if ("har".equals(dst.toUri().getScheme())) {
  throw new UnsupportedOperationException("upload into har is not supported; upload to HDFS then run hadoop archive");
}

When it happens

Trigger: fs.copyFromLocalFile(delSrc, overwrite, localSrc, harDst) with a har:// destination, directly or via FileUtil/FileSystem shell-style upload helpers.

Common situations: Ingestion scripts that push local files to a 'storage' URI later changed to har://; operators trying to add one file to an existing archive by uploading it in place.

Related errors

• Har: create not allowed.
• Har: append not allowed.
• Har: setReplication not allowed
• Har: rename not allowed
• Har: truncate not allowed

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/25134f9e7b3f9315. Report an issue: GitHub.