:我不能當我啓動Rails服務器我得到以下錯誤,啓動軌道服務器
$ rails s -p 8080
from /home/ccuser/.gem/ruby/2.0.0/gems/railties-4.1.1/lib/rails/commands.rb:17:in `<top (required)>'
from /home/ccuser/workspace/learn-rails_threadly/threadly/bin/rails:8:in `require'
from /home/ccuser/workspace/learn-rails_threadly/threadly/bin/rails:8:in `<top (required)>'
from /home/ccuser/.gem/ruby/2.0.0/gems/spring-1.3.6/lib/spring/client/rails.rb:28:in `load'
from /home/ccuser/.gem/ruby/2.0.0/gems/spring-1.3.6/lib/spring/client/rails.rb:28:in `call'
from /home/ccuser/.gem/ruby/2.0.0/gems/spring-1.3.6/lib/spring/client/command.rb:7:in `call'
from /home/ccuser/.gem/ruby/2.0.0/gems/spring-1.3.6/lib/spring/client.rb:26:in `run'
from /home/ccuser/.gem/ruby/2.0.0/gems/spring-1.3.6/bin/spring:48:in `<top (required)>'
from /home/ccuser/.gem/ruby/2.0.0/gems/spring-1.3.6/lib/spring/binstub.rb:11:in `load'
from /home/ccuser/.gem/ruby/2.0.0/gems/spring-1.3.6/lib/spring/binstub.rb:11:in `<top (required)>'
from /usr/lib/ruby/2.0.0/rubygems/core_ext/kernel_require.rb:55:in `require'
from /usr/lib/ruby/2.0.0/rubygems/core_ext/kernel_require.rb:55:in `require'
from /home/ccuser/workspace/learn-rails_threadly/threadly/bin/spring:13:in `<top (required)>'
from bin/rails:3:in `load'
from bin/rails:3:in `<main>'
可能是什麼問題呢?