我尝试了以下命令rhc setup
并显示以下消息
/usr/local/lib/ruby/site_ruby/1.9.1/rubygems/core_ext/kernel_require.rb:45:in `require': cannot load such file -- net/ssh (LoadError)
from /usr/local/lib/ruby/site_ruby/1.9.1/rubygems/core_ext/kernel_require.rb:45:in `require'
from /usr/local/lib/ruby/gems/1.9.1/gems/rhc-1.8.9/lib/rhc/ssh_helpers.rb:18:in `<top (required)>'
from /usr/local/lib/ruby/gems/1.9.1/gems/rhc-1.8.9/lib/rhc/wizard.rb:72:in `<class:Wizard>'
from /usr/local/lib/ruby/gems/1.9.1/gems/rhc-1.8.9/lib/rhc/wizard.rb:6:in `<module:RHC>'
from /usr/local/lib/ruby/gems/1.9.1/gems/rhc-1.8.9/lib/rhc/wizard.rb:5:in `<top (required)>'
from /usr/local/lib/ruby/site_ruby/1.9.1/rubygems/core_ext/kernel_require.rb:45:in `require'
from /usr/local/lib/ruby/site_ruby/1.9.1/rubygems/core_ext/kernel_require.rb:45:in `require'
from /usr/local/lib/ruby/gems/1.9.1/gems/rhc-1.8.9/lib/rhc/commands/base.rb:4:in `<top (required)>'
from /usr/local/lib/ruby/site_ruby/1.9.1/rubygems/core_ext/kernel_require.rb:45:in `require'
from /usr/local/lib/ruby/site_ruby/1.9.1/rubygems/core_ext/kernel_require.rb:45:in `require'
from /usr/local/lib/ruby/gems/1.9.1/gems/rhc-1.8.9/lib/rhc/commands/app.rb:1:in `<top (required)>'
from /usr/local/lib/ruby/site_ruby/1.9.1/rubygems/core_ext/kernel_require.rb:45:in `require'
from /usr/local/lib/ruby/site_ruby/1.9.1/rubygems/core_ext/kernel_require.rb:45:in `require'
from /usr/local/lib/ruby/gems/1.9.1/gems/rhc-1.8.9/lib/rhc/commands.rb:139:in `block in load'
from /usr/local/lib/ruby/gems/1.9.1/gems/rhc-1.8.9/lib/rhc/commands.rb:138:in `each'
from /usr/local/lib/ruby/gems/1.9.1/gems/rhc-1.8.9/lib/rhc/commands.rb:138:in `load'
from /usr/local/lib/ruby/gems/1.9.1/gems/rhc-1.8.9/lib/rhc/cli.rb:35:in `start'
from /usr/local/lib/ruby/gems/1.9.1/gems/rhc-1.8.9/bin/rhc:18:in `<top (required)>'
from /usr/local/bin/rhc:23:in `load'
from /usr/local/bin/rhc:23:in `<main>'
问题是什么?