diff --git a/app/controllers/fluentd/agents_controller.rb b/app/controllers/fluentd/agents_controller.rb
index 2829fe8..bf575f3 100644
--- a/app/controllers/fluentd/agents_controller.rb
+++ b/app/controllers/fluentd/agents_controller.rb
@@ -2,26 +2,29 @@ class Fluentd::AgentsController < ApplicationController
   before_action :find_fluentd
 
   def start
-    unless @fluentd.agent.start
+    if @fluentd.agent.start
+      flash[:success] = t("messages.fluentd_start_stop_delay_notice", action: t('fluentd.common.start'))
+    else
       flash[:error] = t("messages.fluentd_start_failed", brand: fluentd_ui_title) + @fluentd.agent.log_tail(1).first
     end
-    flash[:success] = t("messages.fluentd_start_stop_delay_notice", action: t('fluentd.common.start'))
     redirect_to daemon_path(@fluentd), status: 303 # 303 is change HTTP Verb GET
   end
 
   def stop
-    unless @fluentd.agent.stop
+    if @fluentd.agent.stop
+      flash[:success] = t("messages.fluentd_start_stop_delay_notice", action: t('fluentd.common.stop'))
+    else
       flash[:error] = t("messages.fluentd_stop_failed", brand: fluentd_ui_title)
     end
-    flash[:success] = t("messages.fluentd_start_stop_delay_notice", action: t('fluentd.common.stop'))
     redirect_to daemon_path(@fluentd), status: 303 # 303 is change HTTP Verb GET
   end
 
   def restart
-    unless @fluentd.agent.restart
+    if @fluentd.agent.restart
+      flash[:success] = t("messages.fluentd_start_stop_delay_notice", action: t('fluentd.common.restart'))
+    else
       flash[:error] = t("messages.fluentd_restart_failed", brand: fluentd_ui_title) + @fluentd.agent.log_tail(1).first
     end
-    flash[:success] = t("messages.fluentd_start_stop_delay_notice", action: t('fluentd.common.restart'))
     redirect_to daemon_path(@fluentd), status: 303 # 303 is change HTTP Verb GET
   end