I recently got a request to write a tutorial on how to set up a pre-existing Ghost blog to be served by Apache (the master web server) under the root domain. To add a twist, I will also show how to use Apache as a caching server for the static content of Ghost.

For this tutorial I assume the use of Apache 2.2 running on Ubuntu 12.04 LTS. I also assume a basic knowledge of Ubuntu and Apache. Let's start!

Lets start of with a clean slate. I personally make sure all my packages are updated and current. Good practice and can prevent issues in the future.

Bash 
sudo apt-get update
sudo apt-get upgrade
sudo apt-get autoremove

Now we are going to need to activate some Apache modules. These should be install (not enabled) by default.

Bash 
# Enable to mods if not already enabled
# We use a2enmod as the modern way to enable mods (as opposed to creating symlinks)
sudo a2enmod cache disk_cache rewrite proxy proxy_balancer proxy_http

# Restart apache after any mod changes
sudo service apache2 restart

The mod cache provides the basic framework for any type of caching and does very little on its own. I enabled disk_cache to provide local caching on the disk (we could instead use mem_cache for RAM caching, although I do not recommend this). The mods proxy and proxy_balancer provide the ability to route or proxy requests from Apache to Ghost (Node.js). The mod rewrite will help us streamline the use of proxy and proxy_balancer.

Now lets find what ports Ghost is using. I would use this command if I wasn't sure what port to check.

Bash 
sudo netstat -tlpn | grep node

For me this returns two programs that use Node.js:

Bash 
# netstat -tlpn | grep node
tcp  0  0  127.0.0.1:2368  0.0.0.0:*  LISTEN  1275/node
tcp  0  0  127.0.0.1:6633  0.0.0.0:*  LISTEN  1252/node

The default port for production Ghost is 2368 so the first one looks correct. I personally know that port 6633 is from my Simple::Whois server. When we proxy request in apache we will direct the requests to port 2368 on the interface 127.0.0.1 (or localhost).

Lets get configuring Apache. Now there are many ways to do this. I personally like to keep a list of virtual hosts in one file. Although this is against industry standards, I find this approach prevents my renoun forgetfulness.

If this file does not already exist, lets create a vhost.conf file.

Bash 
cd /etc/apache2
sudo touch vhosts.conf # We like touching files
nano vhosts.conf # or your favorite text editor (you vi guys...)

Copy and paste the following, I'll explain it next.

/etc/apache2/vhosts.conf 
<VirtualHost *:80>

	ServerName			silvenga.com	
	ServerAlias 		www.silvenga.com
	DocumentRoot 		/var/www/ghost/public

	RewriteEngine 		on
	RewriteCond 		%{DOCUMENT_ROOT}/%{REQUEST_FILENAME} !-f
	RewriteRule 		^/(.*)$ balancer://upstream%{REQUEST_URI} [P,QSA,L]

	<Proxy balancer://upstream>
		BalancerMember 	http://127.0.0.1:2368
	</Proxy>

</VirtualHost>

CacheRoot				/var/www/cache
CacheEnable			  disk	 /

In Apache we use VirtualHost for each "virtual server". This allows one Apache server to serve multiple domains at the same time. For simplicity we will create a virtual server for our Ghost blog.

The ServerName directive should be set to your domain. In my case my domain is silvenga.com. I provide aliasing of the common www subdomain with ServerAlias. These should be changed.

DocumentRoot should be set to some public directly. In my Ghost installation folder (/var/www/ghost) I have a folder called public - containing non-ghost files (e.g. robots.txt, sitemap.xml, etc.). Set this to a good location. Wherever Ghost is install is recommended.

RewriteEngine enables direct rewriting of the request URL. This allows us to use RewriteCond and RewriteRule. This is where Apache gets tricky and these lines are commonly "copy and pasted". These two lines basically redirect (or rewrite) requests that do not exist in the /ghost/public to our proxy server. You should not need to change this. I would take a look at the official documentation for more info.

The Proxy directive specifies a list of services to proxy too. We only have one server (ghost). We add that here. If Ghost's port is different, this is the place to assert that. More info can be found here.

For disk caching we need to specify a local location for the cache (CacheRoot). I personally use /var/www/cache. CacheEnable enables disk caching for any address that starts with / - basically any and all requests. I will use /var/www/cache for this tutorial.

After we have this we need to tell Apache there is a unorthodox configuration file.

Bash 
cd /etc/apache2
# Open Apache's main config. 
nano apache2.conf

And add the following lines:

Code 
# Virtual hosts
Include /etc/apache2/vhosts.conf

To make sure that Apache can cache to the folder we gave, we should create it and set the correct permissions.

Bash 
sudo mkdir /var/www/cache

# I assume the Apache is using the default user "www-data"
sudo chown www-data:www-data /var/www/cache

We should be all good. Let's restart and test out configuration.

Bash 
sudo service apache2 restart

Done! Lets take a look and see if Apache is working correctly. Goto your domain listed in the vhost.conf file on the default port 80.

Update: Forgot the mod_proxy_http to provide mod_proxy_balancer support for HTTP. Thanks Jon!