Still very much in the process of learning Rails myself, I have pretty much mastered the process of running Webrick and Mongrel. Granted, it *is* an easy process.However, I wanted to be able to run my own Ruby applications along my other, mostly PHP-based, applications. That’s where the challenge usually begins. If you use a dedicated server process, you end up having to serve your pages from a non-standard port, such as 3000. This typically does not work for users who are behind a proxy. Additionally, this means that the simplest approach is to ignore virtual servers and run each application on a different port.

I was expecting the RoR Wiki to be helpful. And, overall, it really is; but in this case I found it mostly frustrating, due to some of its information being outdated and not really all that synthetic.

And that is why I decided, inspired by that Wiki, to create my own guide. Note that this guide describes using Ruby with mod_fastcgi.
Note that this guide describes using Ruby with mod_fcgid. I am sure that you’ve read that mod_fastcgi wasn’t working properly and this was a real concern, forcing you to instead use Apache proxying with a regular Ruby server. Not anymore. mod_cfgid fixes all that. No need for an additional server, no need for mod_ruby either.

Here we go: the following instructions are for a Linux system and you need to be a superuser.

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Pre-Install

1. Download Ruby-1.8.4.tar.gz and follow the install instructions
   .

or

1. Simply use yum. Syntax:
   yum install ruby
   .
   
2. Get RubyGems from http://rubyforge.org/projects/rubygems/
   Note: rubygems-0.8.11.tgz is recommended,
   rubygems-0.9.x is not compatible with Rails (or vice versa if you prefer)
3. Install RubyGems
4. Install Rails. Super-duper easy syntax:
   gems install rails

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Set up Rail’s environment

1. Create a rails user:
   adduser rails
2. passwd rails
3. Create a web directory:
   cd ~rails
4. chmod a+x .
5. mkdir public_html
6. cd public_html
7. Create the famous cookbook application for the sake of this howto:
   rails cookbook
8. Create your virtual domain. I do not use a control panel, so in my case it looks like this:
   vi /var/name/yourdomainname.com.db
9. And I add a ‘A’ record:
   cookbook 14400 IN A 11.22.33.44

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Build Apache Modules

1. Download and install fcgi. I am using ‘wget’ but any other download tool will work:
   wget http://www.fastcgi.com/dist/fcgi-2.4.0.tar.gz
2. tar zxvf fcgi-2.4.0.tar.gz
3. cd fcgi-2.4.0
4. ./configure
5. make && make install
   .
   
6. Download and install mod_fcgid. I am using ‘links’, which is a text web browser, but feel free to use Firefox or whatnot:
   links “http://prdownloads.sourceforge.net/mod-fcgid/mod_fcgid.2.0.tar.gz?download”
7. tar zxvf mod_fcgid.1.10.tar.gz
8. cd mod_fcgid.1.10
9. Edit Makefile and update the value of top_dir with Apache’s home directory. In my case:
   top_dir = /usr/local/apache
10. make && make install
    .
    
11. Do not forget to retrieve the Ruvy fcgi package:
    gem install fcgi

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Configure Apache

1. Edit httpd.conf
   .
2. Add some optional fcgid settings:
   <IfModule mod_fcgid.c>
   IPCCommTimeout 40
   IPCConnectTimeout 10
   DefaultInitEnv RAILS_ENV production
   SocketPath /tmp/fcgidsock
   </IfModule>
   .
   
3. Tell Apache about your rails directory:
   <Directory /home/rails/public_html>
   Options ExecCGI
   AddHandler fcgid-script .fcgi
   AllowOverride all
   Order allow,deny
   Allow from all
   </Directory>
   Of course, you could setup more than one directory!
   .
4. Add a virtual host, hopefully the first of many:
   <VirtualHost 11.22.33.44:80>
   ServerName cookbook.yourdomainname.com
   ServerAdmin wwwadmin@yourdomainname.com
   DocumentRoot /home/rails/public_html/cookbook/public
   ErrorLog /var/log/httpd/rails_error_log
   Options Indexes ExecCGI FollowSymLinks
   RewriteEngine On
   </VirtualHost>
   Note: ‘RewriteEngine On’ is of utmost importance. If you do not use mod_rewrite, Rails will be unable to route your queries.

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Prepare your cookbook application:

1. Edit ~rails/public_html/cookbook/public/.htaccess
   RewriteRule ^(.*)$ dispatch.cgi [QSA,L]
   becomes:
   RewriteRule ^(.*)$ dispatch.fcgi [QSA,L]
   .
   
2. Avoid nasty ’500′ errors; make sure that Rails can create temporary files, such as cache and session files, and logs:
   chmod -R 777 tmp logs
   Of course, if you can use less permissive masks, even better!
   

Stop! You’re done.
Wasn’t it easy?

If you have any questions, just ask. I may even be able to give you some helpful answer!

Updates

I found out two interesting facts:

1. Being meant for a production environment, fastcgi does what it does best: it caches your scripts. Therefore if you modify, say, a controller, you need to notify dispatch.fcgi before you can see the modified script in action:
   killall -TERM dispatch.fcgi
   .
2. MySQL native bindings were not available in the default distro (?). I added them later:
   gem install mysql — –with-mysql-config=`which mysql_config`