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_chmod.c:38

#include "fuse_impls.h"
#include "fuse_users.h"
#include "fuse_connect.h"

int dfs_chmod(const char *path, mode_t mode)
{
  struct hdfsConn *conn = NULL;
  hdfsFS fs;
  TRACE1("chmod", path)
  int ret = 0;
  dfs_context *dfs = (dfs_context*)fuse_get_context()->private_data;

  assert(path);
  assert(dfs);
  assert('/' == *path);

  ret = fuseConnectAsThreadUid(&conn);
  if (ret) {
    fprintf(stderr, "fuseConnectAsThreadUid: failed to open a libhdfs "
            "connection!  error %d.\n", ret);
    ret = -EIO;
    goto cleanup;
  }
  fs = hdfsConnGetFs(conn);

  if (hdfsChmod(fs, path, (short)mode)) {
    ERROR("Could not chmod %s to %d", path, (int)mode);
    ret = (errno > 0) ? -errno : -EIO;
    goto cleanup;
  }

cleanup:
  if (conn) {
    hdfsConnRelease(conn);
  }

  return ret;

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 chmod 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_chmod.c:38 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/150a29aa8e0b8b8c. Report an issue: GitHub.