apache/hadoop · error · IllegalArgumentException

Unable to parse configuration fs.permissions.umask-mode with

Error message

Unable to parse configuration fs.permissions.umask-mode with value {} as {} umask.

What it means

Error "Unable to parse configuration fs.permissions.umask-mode with value {} as {} umask." thrown in apache/hadoop.

Source

Thrown at hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/permission/FsPermission.java:344

    int umask = DEFAULT_UMASK;
    
    // To ensure backward compatibility first use the deprecated key.
    // If the deprecated key is not present then check for the new key
    if(conf != null) {
      String confUmask = conf.get(UMASK_LABEL);
      try {
        if(confUmask != null) {
          umask = new UmaskParser(confUmask).getUMask();
        }
      } catch(IllegalArgumentException iae) {
        // Provide more explanation for user-facing message
        String type = iae instanceof NumberFormatException ? "decimal"
            : "octal or symbolic";
        String error = "Unable to parse configuration " + UMASK_LABEL
            + " with value " + confUmask + " as " + type + " umask.";
        LOG.warn(error);

        throw new IllegalArgumentException(error);
      }
    }
    
    return new FsPermission((short)umask);
  }

  public boolean getStickyBit() {
    return stickyBit;
  }

  /**
   * Returns true if there is also an ACL (access control list).
   *
   * @return boolean true if there is also an ACL (access control list).
   * @deprecated Get acl bit from the {@link org.apache.hadoop.fs.FileStatus}
   * object.
   */
  @Deprecated

View on GitHub (pinned to 2add963021)

Solutions

1. Set fs.permissions.umask-mode to a valid octal or symbolic umask value (e.g. 022 or 'u=rwx,g=rx,o=rx').
2. Correct the configuration value in core-site.xml so it parses as a umask.

When it happens

Trigger: Thrown when the configuration key fs.permissions.umask-mode contains a value that cannot be parsed as either an octal or symbolic umask at FsPermission.getUMask time.

Common situations: See trigger scenarios.

Understand the failure class

• Parsing and encoding errors: unexpected token, malformed input — why parsers reject input and how to find the real culprit.

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/88f436b5c4741660. Report an issue: GitHub.