title: puma.sock missing in ec2 server after capistrano deployment
body: <p>I am getting the following error in the nginx error logs after deploying production a ruby on rails project through capistrano to an instance on ec2. The amazon public host shows a 502 Bad Gateway nginx/1.10.0 (Ubuntu).
  I followed the tutorial from <a href="https://www.sitepoint.com/deploy-your-rails-app-to-aws/" rel="nofollow noreferrer">https://www.sitepoint.com/deploy-your-rails-app-to-aws/</a>
  It seems the puma.sock is not being created when I run cap production deploy..</p>
  
  <pre><code>2017/06/28 01:09:57 [crit] 12802#12802: *1 connect() to unix:/home/deploy/app_name/shared/tmp/sockets/puma.sock failed (2: No such file or directory) while connecting to upstream, client: 173.198.30.2, server: localhost, request: "GET / HTTP/1.1", upstream: "http://unix:/home/deploy/app_name/shared/tmp/sockets/puma.sock:/", host: "host"
  </code></pre>
  
  <p>The following is in my deploy.rb</p>
  
  <pre><code>set :application, 'app_name'
  set :repo_url, 'git@github.com:github_account/app_name.git' # Edit this to match your repository
  set :branch, :master
  set :deploy_to, '/home/deploy/app_name'
  set :pty, true
  set :linked_files, %w{config/database.yml config/application.yml}
  set :linked_dirs, %w{bin log tmp/pids tmp/cache tmp/sockets vendor/bundle public/system public/uploads}
  set :keep_releases, 5
  set :rvm_type, :user
  set :rvm_ruby_version, 'ruby-2.3.3' # Edit this if you are using MRI Ruby
  
  set :puma_rackup, -&gt; { File.join(current_path, 'config.ru') }
  set :puma_state, "#{shared_path}/tmp/pids/puma.state"
  set :puma_pid, "#{shared_path}/tmp/pids/puma.pid"
  set :puma_bind, "unix://#{shared_path}/tmp/sockets/puma.sock"    #accept array for multi-bind
  set :puma_conf, "#{shared_path}/puma.rb"
  set :puma_access_log, "#{shared_path}/log/puma_error.log"
  set :puma_error_log, "#{shared_path}/log/puma_access.log"
  set :puma_role, :app
  set :puma_env, fetch(:rack_env, fetch(:rails_env, 'production'))
  set :puma_threads, [0, 8]
  set :puma_workers, 0
  set :puma_worker_timeout, nil
  set :puma_init_active_record, true
  set :puma_preload_app, false
  </code></pre>
  
  <p>Please help!
  Thanks in advance!</p>