我在浏览器中运行应用程序时出现此错误。运行Rails + Passenger + Nginx。我已尝试过各种步骤，但仍然存在错误。
Could not find rake-12.0.0 in any of the sources (Bundler::GemNotFound)
/root/.rvm/gems/ruby-2.4.0/gems/bundler-1.15.4/lib/bundler/spec_set.rb:87:in `block in materialize'
/root/.rvm/gems/ruby-2.4.0/gems/bundler-1.15.4/lib/bundler/spec_set.rb:81:in `map!'
/root/.rvm/gems/ruby-2.4.0/gems/bundler-1.15.4/lib/bundler/spec_set.rb:81:in `materialize'
/root/.rvm/gems/ruby-2.4.0/gems/bundler-1.15.4/lib/bundler/definition.rb:159:in `specs'
/root/.rvm/gems/ruby-2.4.0/gems/bundler-1.15.4/lib/bundler/definition.rb:218:in `specs_for'
/root/.rvm/gems/ruby-2.4.0/gems/bundler-1.15.4/lib/bundler/definition.rb:207:in `requested_specs'
/root/.rvm/gems/ruby-2.4.0/gems/bundler-1.15.4/lib/bundler/runtime.rb:109:in `block in definition_method'
/root/.rvm/gems/ruby-2.4.0/gems/bundler-1.15.4/lib/bundler/runtime.rb:21:in `setup'
/root/.rvm/gems/ruby-2.4.0/gems/bundler-1.15.4/lib/bundler.rb:101:in `setup'
/root/.rvm/gems/ruby-2.4.0/gems/bundler-1.15.4/lib/bundler/setup.rb:19:in `<top (required)>'
/usr/local/rvm/rubies/ruby-2.4.0/lib/ruby/site_ruby/2.4.0/rubygems/core_ext/kernel_require.rb:55:in `require'
/usr/local/rvm/rubies/ruby-2.4.0/lib/ruby/site_ruby/2.4.0/rubygems/core_ext/kernel_require.rb:55:in `require'
/usr/share/ruby/vendor_ruby/phusion_passenger/loader_shared_helpers.rb:430:in `activate_gem'
/usr/share/ruby/vendor_ruby/phusion_passenger/loader_shared_helpers.rb:297:in `block in run_load_path_setup_code'
/usr/share/ruby/vendor_ruby/phusion_passenger/loader_shared_helpers.rb:435:in `running_bundler'
/usr/share/ruby/vendor_ruby/phusion_passenger/loader_shared_helpers.rb:296:in `run_load_path_setup_code'
/usr/share/passenger/helper-scripts/rack-preloader.rb:100:in `preload_app'
/usr/share/passenger/helper-scripts/rack-preloader.rb:156:in `<module:App>'
/usr/share/passenger/helper-scripts/rack-preloader.rb:30:in `<module:PhusionPassenger>'
/usr/share/passenger/helper-scripts/rack-preloader.rb:29:in `<main>'