# Config: Common Parameters

Some common parameters are available for all or some of the Fluentd plugins. This page describes these parameters.

## Parameters for all the Plugins

### `@type`

The `@type` parameter specifies the type of the plugin.

```text
<source>
  @type my_plugin_type
</source>

<filter>
  @type my_filter
</filter>
```

### `@id`

The `@id` parameter specifies a unique name for the configuration. It is used as paths for buffer, storage, logging and for other purposes.

```text
<match>
  @type file
  @id service_www_accesslog
  path /path/to/my/access.log
  # ...
</match>
```

This parameter should be specified for all the plugins to enable `root_dir` feature globally.

See also: [System Configuration](../deployment/system-config.md)

### `@log_level`

This parameter specifies the plugin-specific logging level. The default log level is `info`. Global log level can be specified by setting `log_level` in `<system>` section or with `-v/-q` command line arguments. The `@log_level` parameter overrides the logging level only for the specified plugin instance.

```text
<system>
  log_level info
</system>

<source>
  # ...
  @log_level debug # shows debug log only for this plugin
</source>
```

The main purposes of this parameter are:

1. to suppress too many logs for that plugin; and,
2. to show the debug logs to help in the debugging process.

Please see the [logging article](../deployment/logging.md) for further details.

## Plugin Parameters that Emit Events

### @label

The `@label` parameter is to route the input events to `<label>` sections, the set of the `<filter>` and `<match>` subsections under `<label>`.

```text
<source>
  @type ...
  @label @access_logs
  # ...
</source>

<source>
  @type ...
  @label @system_metrics
  # ...
</source>

<label @access_logs>
  <match **>
    @type file
    path ...
  </match>
</label>

<label @system_metrics>
  <match **>
    @type file
    path ...
  </match>
</label>
```

NOTE: The values for the `@label` parameter MUST start with `@` character.

Specifying `@label` is strongly recommended to route events to any plugin without modifying the tags. It helps make the complex configuration modular and simple.