EIO

EIO

Error message

fuseConnectAsThreadUid: failed to open a libhdfs connection!  error %d.

What it means

Error "fuseConnectAsThreadUid: failed to open a libhdfs connection! error %d. " thrown in apache/hadoop.

Source

Thrown at hadoop-hdfs-project/hadoop-hdfs-native-client/src/main/native/fuse-dfs/fuse_impls_open.c:111

  int64_t flagRet;

  TRACE1("open", path)

  // check params and the context var
  assert(path);
  assert('/' == *path);
  assert(dfs);

  // retrieve dfs specific data
  fh = (dfs_fh*)calloc(1, sizeof (dfs_fh));
  if (!fh) {
    ERROR("Malloc of new file handle failed");
    ret = -EIO;
    goto error;
  }
  ret = fuseConnectAsThreadUid(&fh->conn);
  if (ret) {
    fprintf(stderr, "fuseConnectAsThreadUid: failed to open a libhdfs "
            "connection!  error %d.\n", ret);
    ret = -EIO;
    goto error;
  }
  fs = hdfsConnGetFs(fh->conn);
  flagRet = get_hdfs_open_flags(fs, path, fi->flags);
  if (flagRet < 0) {
    ret = -flagRet;
    goto error;
  }
  flags = flagRet;
  if ((fh->hdfsFH = hdfsOpenFile(fs, path, flags,  0, 0, 0)) == NULL) {
    ERROR("Could not open file %s (errno=%d)", path, errno);
    if (errno == 0 || errno == EINTERNAL) {
      ret = -EIO;
      goto error;
    }
    ret = -errno;

View on GitHub (pinned to 2add963021)

Solutions

Verify the user's Kerberos ticket is valid (kinit) and that libhdfs can connect to the NameNode; then retry the open operation.
Check the error code to distinguish authentication failure from configuration problems (CLASSPATH/HADOOP_CONF_DIR).

When it happens

Trigger: Thrown at hadoop-hdfs-project/hadoop-hdfs-native-client/src/main/native/fuse-dfs/fuse_impls_open.c:111 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/bac532a309075611. Report an issue: GitHub.