CentOS-6.4下搭建Rails环境
（1）安装Rails
1）安装需要的Package
# yum -y install gcc
# yum -y install gcc-c++
# yum -y install zlib zlib-devel
# yum -y install readline readline-devel
# yum -y install openssl openssl-devel
最好是 #yum install gcc gcc-c++ openssl* readline* ncurses* zlib* libxml* libjpeg* libpng* libxslt* libtool*
2）安装Ruby
# cd /usr/local/src
# wget ftp://ftp.ruby-lang.org/pub/ruby/2.0/ruby-2.0.0-p247.tar.gz
# tar zxvf ruby-2.0.0-p247.tar.gz
# cd ruby-2.0.0-p247
# ./configure
# make
# make install
# ruby -v
3）更新Gem
# gem update --system
# gem -v
4）安装Rails
# gem install rdoc
# gem install rails
# rails -v
5）卸载Ruby
# cd /usr/local/src/ruby-2.0.0-p247
# cat .installed.list | xargs rm
常见问题
1）问题1（NoMethodError：openssl）
缺什么装什么
# yum install gcc-c++
# yum install curl-devel
# yum install httpd-devel
# yum install apr-devel
# yum install apr-util-devel
再次执行
# passenger-install-apache2-module
3）设置Apache
/etc/httpd/conf/httpd.conf
# yum install sqlite-devel
# cd testapp/
# bundle install
5）创建Scaffold
# rails g scaffold friend name:string address:string
# rake db:create RAILS_ENV=production
# rake db:migrate RAILS_ENV=production
# rake assets:precompile RAILS_ENV=production
6）启动服务
# setenforce 0
# /etc/init.d/httpd restart
http://localhost/friends
（３）Nginx+Unicorn
1）安装Nginx
# rpm -ivh http://nginx.org/packages/centos/6/noarch/RPMS/nginx-release-centos-6-0.el6.ngx.noarch.rpm
# yum install nginx
# /etc/init.d/nginx start
2）安装unicorn
# gem install unicorn
3）创建测试工程
省略，和以上步骤相同
4）设置Unicorn
# cd /var/www/rails/testapp/config/
# wget -O unicorn.rb https://raw.github.com/defunkt/unicorn/master/examples/unicorn.conf.rb
修改模板文件，并创建相应的文件夹
config/unicorn.rb
5）启动服务
# unicorn_rails -c config/unicorn.rb -E production -p 5000 -D
# /etc/init.d/nginx restart
http://localhost:5000/friends
6）设置Ngnix
/etc/nginx/nginx.conf
http://localhost/friends
常见问题
1）问题1（Could not find a JavaScript runtime.）
将CoffeeScript编译成JavaScript需要JavaScript的runtime，
不像Windows或Mac OS X 默认已经有Javascript引擎，Linux下需要安装。
# gem install execjs
# gem install therubyracer
实际是libv8，也可以安装nodejs。JRuby用户更多的使用therubyrhino
2）问题排查2（PassengerWatchdog: Permission denied.）
开启SELinux
# setenforce 0
3）问题排查3（SQLite3::ReadOnlyException:attempt to write a readonly database）
SQLite的数据库文件权限不足
# chmod 777 /db
# chmod 777 databasefilename
# chown user.user databasefilename
