diff --git a/app/models/fluentd/agent/common.rb b/app/models/fluentd/agent/common.rb
index ad14daf..7131554 100644
--- a/app/models/fluentd/agent/common.rb
+++ b/app/models/fluentd/agent/common.rb
@@ -145,8 +145,8 @@ class Fluentd
         end
       end
 
-      def parse_config(config_content)
-        scanner = StringScanner.new(config_content)
+      def parse_config(content)
+        scanner = StringScanner.new(content)
         contents = Hash.new {|h, k| h[k] = [] }
         until scanner.eos? do
           started = scanner.pos