message: docs: fix draining docs
diff: @@ -12,14 +12,13 @@ various events. Draining occurs at the following times:
  * The server is being :ref:`hot restarted <arch_overview_hot_restart>`.
  * Individual listeners are being modified or removed via :ref:`LDS
  <arch_overview_dynamic_config_lds>`.
  -* Admin initiated drain via :ref:`drain_listeners <operations_admin_interface_drain>`.
  Each :ref:`configured listener <arch_overview_listeners>` has a :ref:`drain_type
  <envoy_api_enum_Listener.DrainType>` setting which controls when draining takes place. The currently
  supported values are:
  default
  - Envoy will drain listeners in response to all three cases above (admin drain, hot restart, and
  + Envoy will drain listeners in response to all three cases above (admin health fail, hot restart, and
  LDS update/remove). This is the default setting.
  modify_only
  @@ -34,3 +33,7 @@ level. Currently the only filters that support graceful draining are
  :ref:`HTTP connection manager <config_http_conn_man>`,
  :ref:`Redis <config_network_filters_redis_proxy>`, and
  :ref:`Mongo <config_network_filters_mongo_proxy>`.
  +
  +Listeners can also be stopped via :ref:`drain_listeners <operations_admin_interface_drain>`. In this case,
  +they are directly stopped (with out going through the actual draining process) on worker threads,
  +so that they will not accept any new requests.
  