nginx: [emerg] unknown directive "passenger_enabled"

In my opinion, nginx in a way is better than Apache. It has low memory footprint and configuring it was easier and in straightforward manner. I was helping out a friend who is a Ruby On Rails developer migrating his Apache based server to Nginx couple of days back. When he tried to start nginx server, he got these error messages :

 nginx: [emerg] unknown directive "passenger_enabled" in /etc/nginx/conf.d/default.conf:6
 nginx: configuration file /etc/nginx/nginx.conf test failed

Upon further investigation, the error messages indicate that nginx was compiled without Phusion Passenger support.

To fix this :

sudo gem install passenger

cd /var/lib/gems/1.9.1/gems/passenger-2.2.11/bin

sudo ./passenger-install-nginx-module

restart nginx and the error message is gone.

References :

Phusion Passenger Documentation

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