Configure Nginx as a Reverse Proxy for Apache

Here, we are specifing the steps and configuration needed to run Nginx reverse proxy for Apache. Apache is the most widely used web server software. It is used because of its robust and stable nature, but have main drawback that it consumes a lot of system resources. Hence we need to optimize our webserver for performance, speed and stability.

Nginx is a web server which can also be used as a reverse proxy, load balancer and HTTP cache. It is well-known for its performance and speed, especially when it comes to static contents. Nginx can also be set up to handle dynamic contents using PHP-FPM or similar packages. We are combining the stability and compatibility of Apache along with the performance and speed of Nginx. So that Nginx will be the front end webserver serving the static contents and Apache serves the dynamic contents which of course pulls data from databases and php files. Let us see the steps to use Nginx reverse proxy for the Apache.

STEPS :

1. Install Apache.

2. Configure the Reverse Proxy settings on Apache. 

Now we have to add the virtualhost entry. 

NameVirtualHost 127.0.0.1:81
# Define Server document root
 DocumentRoot /var/www/html/
# Define the virtual host
<VirtualHost 127.0.0.1:81>
 ServerName www.yourwebsite.com
 ServerAlias yourwebsite.com
 DocumentRoot /var/www/yourwebsite.com
 <Directory "/var/www/yourwebsite.com">
 Options FollowSymLinks -Includes
 AllowOverride All
 Order allow,deny
 Allow from all
 </Directory>
 RewriteEngine on
</VirtualHost>

Make sure that you change the name of the domain from ‘yourwebsite.com’ to the name of your actual website, use the assigned IP to the domain and replace ‘127.0.0.1’ above. Also make sure that you enter the actual Document Root as well. 

Now use the Include feature to include the created directory in the httpd.conf. Open the ‘httpd.conf’ and enter the below string.

Restart httpd to apply the changes.

3. Install Nginx.

4. Configure Nginx main configuration. 

Now place the below in the nginx.conf, make sure that you keep a copy of the original conf file before doing this.

Then paste this inside. 

 server {
 listen 80;
 server_name yourwebsite.com yourwebsite.com;
 access_log off;
 error_log logs/yourwebsite.com-error_log crit;
location ~* .(gif|jpg|jpeg|png|ico|wmv|3gp|avi|mpg|mpeg|mp4|flv|mp3|mid|js|css|html|htm|wml)$ {
 root /var/www/yourwebsite.com;
 expires 365d;
 }
location / {
 client_max_body_size 10m;
 client_body_buffer_size 128k;
 proxy_send_timeout 90;
 proxy_read_timeout 90;
 proxy_buffer_size 128k;
 proxy_buffers 4 256k;
 proxy_busy_buffers_size 256k;
 proxy_temp_file_write_size 256k;
 proxy_connect_timeout 30s;
 proxy_redirect http://www.yourwebsite.com:81 http://www.yourwebsite.com;
 proxy_redirect http://yourwebsite.com:81 http://yourwebsite.com;
 proxy_pass http://127.0.0.1:81/;
 proxy_set_header Host $host;
 proxy_set_header X-Real-IP $remote_addr;
 proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
 }
 location ~ /\.ht {
 deny all;
 }
}

Make sure that you change the name of the domain from ‘yourwebsite.com’ to the name of your actual website, use the assigned IP to the domain and replace ‘127.0.0.1’ above. Also make sure that you enter the actual Document Root as well.

location ~* .(gif|jpg|jpeg|png|ico|wmv|3gp|avi|mpg|mpeg|mp4|flv|mp3|mid|js|css|html|htm|wml)$ {
  root /var/www/yourwebsite.com;
  expires 365d;
  }

b. Then we added the reverse proxy configuration so Nginx can serve the information from xxx.xx.xx.xx:81, which is the port and IP where Apache is listening to.
c. Finally the “location ~ /\.ht {” location block denies access to .htaccess files, if Apache’s document root
concurs with nginx’s one.

 6. Now we have to install the reverse proxy add forward module for Apache (mod_rpaf).

mod_rpaf will help Apache to know who connects to it (otherwise the only IP address you will see in your logs is 127.0.0.1. It changes the remote address of the client visible to other Apache modules when two conditions are satisfied. First condition is that the remote client is actually a proxy that is defined in httpd.conf. Secondly if
there is an incoming X-Forwarded-For header and the proxy is in it’s list of known proxies it takes the last IP from the incoming X-Forwarded-For header and changes the remote address of the client in the request structure. It also takes the incoming X-Host header and updates the virtualhost settings accordingly. For Apache2 mod_proxy it takes the X-Forwared-Host header and updates the virtualhosts.

  cd /usr/local/src
  wget https://github.com/y-ken/mod_rpaf/archive/master.zip
  unzip master.zip
  cd mod_rpaf-master/
  apxs -i -c -n mod_rpaf-2.0.so mod_rpaf-2.0.c

Once the installation is complete we need to add a new configuration file for mod_rpaf.

  vi /etc/httpd/conf.d/rpaf.conf 

Now paste the below snippet inside the rpaf connf file.

LoadModule rpaf_module modules/mod_rpaf-2.0.so
  RPAFenable On
  RPAFsethostname On
  RPAFproxy_ips 127.0.0.1 YOUR.SERVER.IP

Replace ‘YOUR.SERVER.IP’ with your actual server IP.

Now restart httpd to apply the changes.

 service httpd restart

Now we can test whether the setting is actually working. Use the below command in a machine with curl utility installed.

 curl -Is http://yourwebsite.com 

 vi /var/www/yourwebsite.com/info.php