OpenShift でのログファイルのローテーション後、fluentd 1.14.x in_tail プラグインが動作を停止する

Issue

• OpenShift でのログファイルのローテーション後、fluentd 1.14.x in_tail プラグインが動作を停止します。

• fluentd コレクター Pod で以下のエラーが表示されました。

  [error]: [container-input] undefined method `unwatched=' for nil:NilClass
  [error]: /usr/local/share/gems/gems/fluentd-1.14.6/lib/fluent/plugin/in_tail.rb:512:in `update_watcher'
  [error]: /usr/local/share/gems/gems/fluentd-1.14.6/lib/fluent/plugin/in_tail.rb:881:in `call'
  [error]: /usr/local/share/gems/gems/fluentd-1.14.6/lib/fluent/plugin/in_tail.rb:881:in `on_rotate'
  [error]: /usr/local/share/gems/gems/fluentd-1.14.6/lib/fluent/plugin/in_tail.rb:1180:in `on_notify'
  [error]: /usr/local/share/gems/gems/fluentd-1.14.6/lib/fluent/plugin/in_tail.rb:814:in `on_notify'
  [error]: /usr/local/share/gems/gems/fluentd-1.14.6/lib/fluent/plugin/in_tail.rb:401:in `block in setup_watcher'
  [error]: /usr/local/share/gems/gems/fluentd-1.14.6/lib/fluent/plugin/in_tail.rb:734:in `on_change'
  [error]: /usr/local/share/gems/gems/cool.io-1.7.1/lib/cool.io/loop.rb:88:in `run_once'
  [error]: /usr/local/share/gems/gems/cool.io-1.7.1/lib/cool.io/loop.rb:88:in `run'
  [error]: /usr/local/share/gems/gems/fluentd-1.14.6/lib/fluent/plugin_helper/event_loop.rb:93:in `block in start'
  [error]: /usr/local/share/gems/gems/fluentd-1.14.6/lib/fluent/plugin_helper/thread.rb:78:in `block in thread_create'