Rendering D：/new/ruby/gems/1.8/gems/actionpack-2.0.2/lib/action_controller/templates/rescues/layout.erb(not_found)

I am using Instant rails to establish a website on which there is basic information开发者_如何学JAVA about commodities. To achieve that,I typed the following cmds.

rails mebay
cd mebay
ruby script/generate model ad name:string description:text price:decimal seller_id:integer email:string img_url:string
rake db:migrate
ruby script/generate controller ads

then I create a file show.html.erb,later I add the code

map.connect '/ads/:id', :controller=>'ads', :action=>'show'

in the config/route.rb then I start the server,but it turns out "unknown action to show" on the webpage. And in the command appears the words in the title

ok this comments discussion is much longer than i anticipated

what you pasted into title of this question is only small part of error that rails shows you in console where you started rails application

i don't know how to put it more clearly - copy paste full error dump from either console where you started rails application or from your /log/development.log file. you did copy "/new/ruby/gems/1.8/gems/actionpack-2.0.2/lib/action_controller/templates/rescues/layout.erb(not_found)" from somewhere didn't you?