Redmine in Apache shows Blank Page - ruby-on-rails

Question

I've just tried to configure Redmine on my Apache server, as folows:
Files in /var/www/redmine.my.domain
In /etc/apache2/sites-available/redmine.my.domain.conf
<VirtualHost *:80>
# The ServerName directive sets the request scheme, hostname and port that
# the server uses to identify itself. This is used when creating
# redirection URLs. In the context of virtual hosts, the ServerName
# specifies what hostname must appear in the request's Host: header to
# match this virtual host. For the default virtual host (this file) this
# value is not decisive as it is used as a last resort host regardless.
# However, you must set it for any further virtual host explicitly.
ServerName redmine.my.domain
ServerAdmin webmaster#localhost
DocumentRoot /var/www/redmine.my.domain/public/
<Directory />
Options FollowSymLinks
AllowOverride None
</Directory>
# Available loglevels: trace8, ..., trace1, debug, info, notice, warn,
# error, crit, alert, emerg.
# It is also possible to configure the loglevel for particular
# modules, e.g.
#LogLevel info ssl:warn
ErrorLog ${APACHE_LOG_DIR}/error.log
CustomLog ${APACHE_LOG_DIR}/access.log combined
# For most configuration files from conf-available/, which are
# enabled or disabled at a global level, it is possible to
# include a line for only one particular virtual host. For example the
# following line enables the CGI configuration for this host only
# after it has been globally disabled with "a2disconf".
#Include conf-available/serve-cgi-bin.conf
<Directory /var/www/redmine.my.domain/public>
Options Indexes ExecCGI FollowSymLinks
Order allow,deny
Allow from all
AllowOverride all
Options Indexes FollowSymLinks MultiViews
</Directory>
</VirtualHost>
# vim: syntax=apache ts=4 sw=4 sts=4 sr noet
It only shows a blank page. Does anyone know what may be missing?

Answer 1

Redmine is RoR (Ruby on Rails) application, for usage and installation, official wiki should be followed since there are multiple steps and ways to run it on different platforms. Cick here and find the best way for your case.
In order to run it via Apache you must either run it as CGI/FCGI which is not very common way.
Or to run it via PhusionPassenger Apache module or PhusionPassenger standalone.
One common way to run it is via some Ruby app server like Puma, Unicorn, Webrick or Thin, then Apache or Ngnix reverse proxy it.
As stated earlier, various methods to run it, depending upon platform are described in official wiki.