apache/hadoop · error · RuntimeException

Unable to determine current user

Error message

Unable to determine current user

What it means

Error "Unable to determine current user" thrown in apache/hadoop.

Source

Thrown at hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/conf/Configuration.java:296

    public boolean isParserRestricted() {
      return restrictParser;
    }

    @Override
    public String toString() {
      return name;
    }

    private static boolean getRestrictParserDefault(Object resource) {
      if (resource instanceof String || !UserGroupInformation.isInitialized()) {
        return false;
      }
      UserGroupInformation user;
      try {
        user = UserGroupInformation.getCurrentUser();
      } catch (IOException e) {
        throw new RuntimeException("Unable to determine current user", e);
      }
      return user.getRealUser() != null;
    }
  }
  
  /**
   * List of configuration resources.
   */
  private ArrayList<Resource> resources = new ArrayList<Resource>();
  
  /**
   * The value reported as the setting resource when a key is set
   * by code rather than a file resource by dumpConfiguration.
   */
  static final String UNKNOWN_RESOURCE = "Unknown";


  /**

View on GitHub (pinned to 2add963021)

Solutions

1. Ensure the SecurityContext/UserGroupInformation is initialized (call UserGroupInformation.loginUserFromSubject or run within an authenticated context) before retrieving the current user.

Example fix

UserGroupInformation.getCurrentUser() after a successful login.

When it happens

Trigger: Raised at runtime when the documented precondition or configuration requirement for this operation is violated.

Common situations: Misconfigured or missing property, invalid user input, or calling the API before its prerequisites are met.

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/66f8c2c5222dee8e. Report an issue: GitHub.