Installing Passenger (mod_rails): “Command not found”

If you’re installing Passenger (aka: mod_rails) and you hit the following error at the stage in which you run passenger-install-apache2-module:

sudo: passenger-install-apache2-module: command not found

all this means is that you don’t have the gems bin directory in your PATH so do this instead:

sudo /var/lib/gems/1.8/bin/passenger-install-apache2-module