Nginx phusion_passenger throws a configuration template error: unknown directive “passenger_root”

Symptoms

After installing NodeJS component, the following error is shown at Plesk Home page:

PLESK_ERROR: Apache config (14816524790.56007300) generation failed: Template_Exception: nginx: [emerg] unknown directive “passenger_root” in /etc/nginx/conf.d/phusion-passenger.conf:1
nginx: configuration file /etc/nginx/nginx.conf test failed

Cause

Nginx misconfiguration.

Resolution

1. Connect to the server using SSH.

2. Use any text editor to add the following directive into /etc/nginx/nginx.conf file right before the events { part:

   include /etc/nginx/modules.conf.d/*.conf;

   The result should looks like on the screenshot:
   

   Warning: Make sure that it is added before other configurations includes (for example right after pid file), to load all modules before directive(s) used by some particular module will be declared.

3. Make sure that configuration file /etc/nginx/modules.conf.d/phusion-passenger.conf which is loading phusion passenger module exists and has the following content:

   # cat /etc/nginx/modules.conf.d/phusion-passenger.conf
   load_module nginx/modules/ngx_http_passenger_module.so;

4. Restart nginx service:

   # service nginx restart