apache/hadoop · error · HadoopIllegalArgumentException

Uri without authority: {uri}

Error message

Uri without authority: {uri}

What it means

Thrown from the URI-formatting logic of the AbstractFileSystem constructor: a file system registered with authorityNeeded=true (e.g. hdfs, which must know which NameNode to talk to) was constructed from a URI whose authority component is null, such as hdfs:///. At this layer Hadoop cannot guess a NameNode for you, so instance creation fails immediately with HadoopIllegalArgumentException.

Source

Thrown at hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/AbstractFileSystem.java:329

   * 
   * @return URI of the file system
   * 
   * @throws URISyntaxException <code>uri</code> has syntax error
   */
  private URI getUri(URI uri, String supportedScheme,
      boolean authorityNeeded, int defaultPort) throws URISyntaxException {
    checkScheme(uri, supportedScheme);
    // A file system implementation that requires authority must always
    // specify default port
    if (defaultPort < 0 && authorityNeeded) {
      throw new HadoopIllegalArgumentException(
          "FileSystem implementation error -  default port " + defaultPort
              + " is not valid");
    }
    String authority = uri.getAuthority();
    if (authority == null) {
       if (authorityNeeded) {
         throw new HadoopIllegalArgumentException("Uri without authority: " + uri);
       } else {
         return new URI(supportedScheme + ":///");
       }   
    }
    // authority is non null  - AuthorityNeeded may be true or false.
    int port = uri.getPort();
    port = (port == -1 ? defaultPort : port);
    if (port == -1) { // no port supplied and default port is not specified
      return new URI(supportedScheme, authority, "/", null);
    }
    return new URI(supportedScheme + "://" + uri.getHost() + ":" + port);
  }
  
  /**
   * The default port of this file system.
   * 
   * @return default port of this file system's Uri scheme
   *         A uri with a port of -1 =&gt; default port;

View on GitHub (pinned to 2add963021)

Solutions

1. Add the authority to the URI: hdfs://namenode:8020/path, or for HA the logical name hdfs://myNameservice/path
2. Fix the configuration source of the URI (fs.defaultFS, mount table entries, job.xml) so it includes host:port or nameservice
3. For custom file systems: pass authorityNeeded=false to the AbstractFileSystem constructor if the scheme genuinely has no authority
4. Qualify relative/authority-less paths against a correctly configured default FS (Path.makeQualified / FileContext.fixRelativePart) before resolving them

Example fix

// before
AbstractFileSystem afs = AbstractFileSystem.get(new URI("hdfs:///"), conf); // Uri without authority: hdfs:///

// after
AbstractFileSystem afs = AbstractFileSystem.get(new URI("hdfs://ns1/"), conf); // HA logical authority

URI u = path.toUri();
if (u.getScheme() != null && u.getAuthority() == null && schemeRequiresAuthority(conf, u.getScheme())) {
  // rebuild with the configured default authority before touching the FS
  URI def = FileSystem.getDefaultUri(conf);
  u = new URI(u.getScheme(), def.getAuthority(), u.getPath(), null, null);
  path = new Path(u);
}

try { AbstractFileSystem.get(uri, conf); } catch (HadoopIllegalArgumentException e) { if (e.getMessage().startsWith("Uri without authority")) { /* fix uri/config, retry once */ } else throw e; }

When it happens

Trigger: AbstractFileSystem.get(new URI("hdfs:///"), conf), FileContext.getFileContext(...) resolving a Path like new Path("hdfs:///data/x") through FileContext#getFSofPath, or a custom AbstractFileSystem subclass calling super(uri, scheme, true, port) with an authority-less URI.

Common situations: fs.defaultFS (or a viewfs mount-table entry) configured as "hdfs:///" with the namenode host:port omitted; URIs built by string concatenation that drop the authority; code ported from file:/// (which needs no authority) to hdfs; HA setups where the logical nameservice id was left out of the URI.

Related errors

• Wrong FS: {path}, expected: {this.getUri()}
• Bad configuration of hadoop.security.key.provider.path at ${
• Wrong FS: {path} and port={thatPort}, expected: {this.getUri
• No scheme in default FS: ${uri}
• Could not initialize target File System for URI : {targetDir

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/8642610887f7b34d. Report an issue: GitHub.