无法在Rails 5中启动Rails服务器

Question

我使用RVM安装了Rails。 一切正常，就像用rails new app生成一个新应用rails new app 。 bundle install ，其他所有命令也可以正常运行。 但是，当我使用rails -server启动我的Rails服务器时，出现以下错误，我无法理解。

rails aborted!
NameError: undefined local variable or method `rver' for #<Rake::Application:0x00563aa7540988>
/home/mrrobot/.rvm/gems/ruby-2.4.0@global/gems/railties-5.0.2/lib/rails/commands/rake_proxy.rb:12:in `block in run_rake_task'
/home/mrrobot/.rvm/gems/ruby-2.4.0@global/gems/railties-5.0.2/lib/rails/commands/rake_proxy.rb:11:in `run_rake_task'
/home/mrrobot/.rvm/gems/ruby-2.4.0@global/gems/railties-5.0.2/lib/rails/commands/commands_tasks.rb:51:in `run_command!'
/home/mrrobot/.rvm/gems/ruby-2.4.0@global/gems/railties-5.0.2/lib/rails/commands.rb:18:in `<top (required)>'
/home/mrrobot/rails/demo/app/bin/rails:9:in `require'
/home/mrrobot/rails/demo/app/bin/rails:9:in `<top (required)>'
/home/mrrobot/.rvm/gems/ruby-2.4.0@global/gems/spring-2.0.1/lib/spring/client/rails.rb:28:in `load'
/home/mrrobot/.rvm/gems/ruby-2.4.0@global/gems/spring-2.0.1/lib/spring/client/rails.rb:28:in `call'
/home/mrrobot/.rvm/gems/ruby-2.4.0@global/gems/spring-2.0.1/lib/spring/client/command.rb:7:in `call'
/home/mrrobot/.rvm/gems/ruby-2.4.0@global/gems/spring-2.0.1/lib/spring/client.rb:30:in `run'
/home/mrrobot/.rvm/gems/ruby-2.4.0@global/gems/spring-2.0.1/bin/spring:49:in `<top (required)>'
/home/mrrobot/.rvm/gems/ruby-2.4.0@global/gems/spring-2.0.1/lib/spring/binstub.rb:31:in `load'
/home/mrrobot/.rvm/gems/ruby-2.4.0@global/gems/spring-2.0.1/lib/spring/binstub.rb:31:in `<top (required)>'
/home/mrrobot/rails/demo/app/bin/spring:15:in `require'
/home/mrrobot/rails/demo/app/bin/spring:15:in `<top (required)>'
bin/rails:3:in `load'
bin/rails:3:in `<main>'
(See full trace by running task with --trace)

Ruby版本：2.4.0p0（2016-12-24修订版57164）[x86_64-linux]

Rails版本：5.0.2

RubyGems版本：2.6.11

Answer 1

它是rails server ，没有破折号

要不就

rails s