rails sが通らない

rails sが通らないAWSのAmazon Linuxにrailsをインストールしてrails sしたらこんなエラーが Warning: You're using Rubygems 2.0.14 with Spring. Upgrade to at least Rubygems 2.1.0 and run `gem pristine --all` for better startup performance. bin/rails:6: warning: already initialized constant APP_PATH /root…