Sorry, I misread the post. Yes, as you pointed above, Varnish itself does not support SSL.
If you want to use HTTPS with Varnish, you need something like this schema:
HTTPS => Varnish => Webserver (Apache)
So, you need a software which is able to handle HTTPS requests and forward them over HTTP to Varnish. As @dgonzalez pointed above, you don't need to install Nginx, as Apache is already able to do it and it is already installed and configured in your WordPress Stack.
This article explains how to configure Apache and Varnish to do these redirections. I think that it covers all your needs.
Basically, you have to change your Apache SSL configuration to do this redirection. Note the:
ProxyPass / http://127.0.0.1:80/
in the SSL VirtualHost.
So, you have to follow this article with some minor changes (related to the Bitnami installation itself).
The article points to
/etc/apache2/sites-available/example.com-ssl to change the Apache configuration. In your case, you have to change it in
Later, in order to these changes to take effect, you have to include this file in
/opt/bitnami/apache2/conf/bitnami/bitnami-apps-vhosts.conf. This file should be empty by default and you have to add this line:
Once this is done (and the rest of the changes related to Varnish), don't forget to restart the servers.
sudo /opt/bitnami/ctlscript.sh restart apache
sudo /opt/bitnami/ctlscript.sh restart varnish
I hope it helps.