HOWTO: Redirect iPhone/iPod Users on Nginx

I learned a little something about nginx, a small footprint web server ideal for serving mobile sites, or sites where you don’t want the heavy overhead of Apache.

While I was serving in a DevOps role at Armor Games, I needed to redirect iPhone/iPod users to a different URL for a promotion. Since nginx at the time didn’t have the ability to utilize mod_rewrite rules, I had to learn how to enable redirection at the server level.

Since nginx was already compiled with redirection support, I had to locate the correct configuration file and add a few lines of code, and away it went.

First, I reviewed /etc/nginx/ and opened the site configuration file within the sites-enabled/ path. For this example, let’s say the site was m.iandouglas.com:

$ vi /etc/conf/nginx/sites-enabled/m.iandouglas.com

In here, I’d look for the ‘server' block and add my redirection rules:

server {
  listen       80;
  server_name  m.iandouglas.com;
  root         /var/www/m.iandouglas.com/public;

  # redirect iPhone/iPod users to the new iphone site
  if ($http_user_agent ~* '(iPhone|iPod|iPad)') {
    rewrite ^/$ http://m.iandouglas.com/iphone/index.html;
  }

Then a simple nginx reload:

$ /etc/init.d/nginx reload

… and we were all set.