Add more one rails env to nginx

rails_env_nginx

$ cp /etc/nginx/sites-available/default /etc/nginx/sites-available/staging
$ ln -s /etc/nginx/sites-available/staging /etc/nginx/sites-enabled/staging

$ nano /etc/nginx/sites-available/staging 

server {

  listen 80;
  listen [::]:80;

  root /home/deploy/myapp_staging/current/public;
  rails_env staging;

  passenger_enabled on;

  server_name staging.myapp.com;
}

$ service nginx restart

# if it has some errors
$ cat /var/log/nginx/error.log