the value "-" for `inline_config` is deprecated. See https:/

Error message

the value "-" for `inline_config` is deprecated. See https://github.com/fluent/fluentd/issues/2711

What it means

Error "the value "-" for `inline_config` is deprecated. See https://github.com/fluent/fluentd/issues/2711" thrown in fluent/fluentd.

Source

Thrown at lib/fluent/supervisor.rb:805

        MessagePackFactory.init(enable_time_support: @system_config.enable_msgpack_time_support)
        Fluent::Engine.init(@system_config, start_in_parallel: ENV.key?("FLUENT_RUNNING_IN_PARALLEL_WITH_OLD"))
        Fluent::Engine.run_configure(@conf)
        enable_ruby_jit if @system_config.enable_jit
        Fluent::Engine.run
        self.class.cleanup_socketmanager_path if @standalone_worker
        exit 0
      end
    end

    def configure(supervisor: false)
      setup_global_logger(supervisor: supervisor)

      if @show_plugin_config
        show_plugin_config
      end

      if @inline_config == '-'
        $log.warn('the value "-" for `inline_config` is deprecated. See https://github.com/fluent/fluentd/issues/2711')
        @inline_config = STDIN.read
      end
      parsed_files = Set.new
      @conf = Fluent::Config.build(
        config_path: @config_path,
        encoding: @conf_encoding,
        additional_config: @inline_config,
        use_v1_config: @use_v1_config,
        type: @config_file_type,
        on_file_parsed: ->(path) { parsed_files << path },
      )
      @system_config = build_system_config(@conf)

      # `<system> umask` sets the process umask, just like the `--umask` command
      # line option. The command line option takes precedence when both are given.
      if @system_config.umask && !@cl_opt.key?(:chumask)
        @chumask = @system_config.umask
      end

View on GitHub (pinned to dd45c6e18d)

When it happens

Trigger: Thrown at lib/fluent/supervisor.rb:805 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of fluent/fluentd@dd45c6e18d (2026-08-21). Data as JSON: /api/errors/dde1027d04315241. Report an issue: GitHub.