有三台机器，操作系统都是CentOS 6.3 64位：其中172.16.9.100，安装Nginx服务器；另外的两台172.16.9.101和172.16.9.102安装unicorn，作为RoR的应用服务器。在这里先保证ruby及rails已经在101和102两台机器上配置好，这是前提。如何安装Nginx及RoR的环境就不在这里说了，很多文章都介绍得很详细。
这里假设项目在/var/www/demo_project文件夹中
在101上使用
gem install unicorn 命令安装unicorn。
新建内容为以下的一个文件，需要进行修改的地方请看文件中的中文注释，文件放置到/var/www/demo_project_unicorn.rb，这个文件是对这个项目的生产环境配置
# Sample verbose configuration file for Unicorn (not Rack)
#
# This configuration file documents many features of Unicorn
# that may not be needed for some applications. See
# http://unicorn.bogomips.org/examples/unicorn.conf.minimal.rb
# for a much simpler configuration file.
#
# See http://unicorn.bogomips.org/Unicorn/Configurator.html for complete
# documentation.
# Use at least one worker per core if you're on a dedicated server,
# more will usually help for _short_ waits on databases/caches.
worker_processes 4
# Since Unicorn is never exposed to outside clients, it does not need to
# run on the standard HTTP port (80), there is no reason to start Unicorn
# as root unless it's from system init scripts.
# If running the master process as root and the workers as an unprivileged
# user, do this to switch euid/egid in the workers (also chowns logs):
# user "unprivileged_user", "unprivileged_group"
# Help ensure your application will always spawn in the symlinked
# "current" directory that Capistrano sets up.
working_directory "/var/www/demo_project" # available in 0.94.0+ 在这里修改为项目所在目录
# listen on both a Unix domain socket and a TCP port,
# we use a shorter backlog for quicker failover when busy
listen "/var/tmp/.unicorn.sock", :backlog => 64
listen 19527, :tcp_nopush => true #端口号，NginX需要用到此端口号
# nuke workers after 30 seconds instead of 60 seconds (the default)
timeout 120
# feel free to point this anywhere accessible on the filesystem
pid "/usr/tmp/demo_project/pids/unicorn.pid" #pid文件的位置，可以自己设置，注意权限
# By default, the Unicorn logger will write to stderr.
# Additionally, ome applications/frameworks log to stderr or stdout,
# so prevent them from going to /dev/null when daemonized here:
stderr_path "/usr/tmp/demo_project/log/unicorn.stderr.log" #错误日志的位置，自己设置，注意权限
stdout_path "/usr/tmp/demo_project/log/unicorn.stdout.log" #输出日志的位置，自己设置，注意权限
# combine Ruby 2.0.0dev or REE with "preload_app true" for memory savings
# http://rubyenterpriseedition.com/faq.html#adapt_apps_for_cow
preload_app true
GC.respond_to?(:copy_on_write_friendly=) and
GC.copy_on_write_friendly = true
# Enable this flag to have unicorn test client connections by writing the
# beginning of the HTTP headers before calling the application. This
# prevents calling the application for connections that have disconnected
# while queued. This is only guaranteed to detect clients on the same
# host unicorn runs on, and unlikely to detect disconnects even on a
# fast LAN.
check_client_connection false
before_fork do |server, worker|
# the following is highly recomended for Rails + "preload_app true"
# as there's no need for the master process to hold a connection
defined?(ActiveRecord::Base) and
ActiveRecord::Base.connection.disconnect!
# The following is only recommended for memory/DB-constrained
# installations. It is not needed if your system can house
# twice as many worker_processes as you have configured.
#
# # This allows a new master process to incrementally
# # phase out the old master process with SIGTTOU to avoid a
# # thundering herd (especially in the "preload_app false" case)
# # when doing a transparent upgrade. The last worker spawned
# # will then kill off the old master process with a SIGQUIT.
# old_pid = "#{server.config[:pid]}.oldbin"
# if old_pid != server.pid
# begin
# sig = (worker.nr + 1) >= server.worker_processes ? :QUIT : :TTOU
# Process.kill(sig, File.read(old_pid).to_i)
# rescue Errno::ENOENT, Errno::ESRCH
# end
# end
#
# Throttle the master from forking too quickly by sleeping. Due
# to the implementation of standard Unix signal handlers, this
# helps (but does not completely) prevent identical, repeated signals
# from being lost when the receiving process is busy.
# sleep 1
end
after_fork do |server, worker|
# per-process listener ports for debugging/admin/migrations
# addr = "127.0.0.1:#{9293 + worker.nr}"
# server.listen(addr, :tries => -1, :delay => 5, :tcp_nopush => true)
# the following is *required* for Rails + "preload_app true",
defined?(ActiveRecord::Base) and
ActiveRecord::Base.establish_connection
# if preload_app is true, then you may also want to check and
# restart any other shared sockets/descriptors such as Memcached,
# and Redis. TokyoCabinet file handles are safe to reuse
# between any number of forked children (assuming your kernel
# correctly implements pread()/pwrite() system calls)
end然后创建一个shell文件，内容如下，这个文件命名为/var/www/unicorn.sh
UNICORN=/usr/local/ruby/bin/unicorn_rails
killall -9 unicorn_rails
$UNICORN -c /var/www/demo_project_unicorn.rb -D -E production其中第一行，指明unicorn的安装位置，unicorn安装成功后，是和ruby，rails等可执行文件是在同一个文件夹中的。第二行，关闭unicorn_rails的进程。第三行，根据-c参数后的配置，在生产环境中启动项目。执行这个文件就能启动unicorn服务器。
另外的一台主机102的配置，也与101相同。unicorn的配置也就完成了。下面开始NginX的配置
在/usr/local/nginx/conf/nginx.conf中添加如下的配置信息，具体意思见中文注释
upstream demo_project_backend {
#连接两台RoR unicorn服务器
server 172.16.9.101:19527;
server 172.16.9.102:19527;
}
server {
listen 80 default_server;
server_name _;
return 403;
}
server {
listen 80;
server_name www.demo_project.com demo_project.com;
#access_log logs/host.access.log main;
proxy_connect_timeout 500s;
proxy_read_timeout 500s;
proxy_send_timeout 500s;
#将对的请求，转到两台主机上
location / {
root html;
index index.html index.htm;
proxy_pass http://demo_project_backend;
}
# redirect server error pages to the static page /50x.html
#
error_page 500 502 503 504 /50x.html;
location = /50x.html {
root html;
}
}来源：oschina
链接：https://my.oschina.net/u/617354/blog/299890