1、/data/drolay11/lcb_saas/tmp/build-147274463612855/vendor/bundle/ruby/2.1.0/bin/rake: symbol lookup error: /data/drolay11/lcb_saas/tmp/build-147274463612855/vendor/bundle/ruby/2.1.0/gems/mysql2-0.3.17/lib/mysql2/mysql2.so: undefined symbol: mysql_get_client_info
這種問題可能是ruby版本沖突引起的。刪除所有的ruby，重新安裝。mysql2用0.3.13的。
2、.rvm/gems/ruby-2.1.5/bin/bundle:22:in `<main>': undefined method `activate_bin_path' for Gem:Module (NoMethodError)
gem install rubygems-updateupdate_rubygems
or
ruby --disable-gems -S update_rubygems
3、NoMethodError: undefined method `spec' for nil:NilClass
An error occurred while installing carrierwave (0.11.0), and Bundler cannot continue.
Make sure that `gem install carrierwave -v '0.11.0'` succeeds before bundling.gem
gem uninstall bundler
gem install bundler 就是安裝新版的bundler
4、.rvm/wrappers/ruby-2.1.5/rake nginx:clean nginx RELEASE=yes
rake aborted!
LoadError: cannot load such file -- rubygems/builder
gem install passenger --version 4.0.0.rc6
5、%u轉化為漢字的問題：
如：迷戀你娘 %u8FF7%u604B%u4F60%u5A18
s = "%u8FF7%u604B%u4F60%u5A18"
b = s.split("%u")-[""]
b.map{|t| [t.to_i(16)].pack("U")}.join
6、Bundler::GemspecError: Could not read gem at /XXX-1.8.2.gem. It may be corrupted.
刪除cache里的文件，重新bundle install
7、國際化時如果有目錄，配置文件的寫法也是用目錄形式，比如： admin/user: