Issues encountered

The instructions I followed were clearly very well written because I encountered very few.

My first attempt to get to my newly configured site resulted in a "502 Bad Gateway" error from nginx

Checking the error log for the website, showed that there was mis-matched config files for the location of unix socket for php-fpm.

/etc/php-fpm.d/www.conf had listen = /var/run/php-fpm/php-fpm.sock

The error indicated that /var/run/php-fpm.sock could not be found - nginx was looking for a different socket file.

This is configured in upstream_phpcgi_unix.conf (called from nginx.conf where you set which upstream handler you are using, tcp or unix sockets)

I made them both /var/run/php-fpm/php-fpm.sock

Restart nginx and I got another error:

"Unable to open primary script: /var/www/sites/ (No such file or directory)"

This was because I hadn't correctly set the root directory of my site in the conf file for this site. Change it to

/var/www/vhosts/ (the root of the drupal installation)

Restart nginx again. Site now work. Hooray.