Varnish is a web application accelerator that provides an easy speed increase to most web applications and Drupal is no exception. It works by creating a reverse proxy service that sits in front of your web server and caches traffic that comes through it.
Many systems and applications require certain access to certain ports and protocols. When installing these systems using Ansible it is necessary to also open up the needed ports so that the systems can function correctly. As there is no iptables module in Ansible the shell command is needed to add the iptables rules.
When setting up staging sites or similar I often add a simple Apache authentication check in order to stop everyone from viewing the site. This is also useful in stopping search engine spiders from accessing a site with testing content on it, which generally causes trouble. It isn't amazingly secure, but it keeps almost everyone out.
Phing is an awesome tool for automating things and I use it more and more for automating all kinds of different tasks. One of the tasks that I don't tend to do all that much is setting up a new local virtual host for Apache on my development machines.
Use the following rules in your Apache configuration (or your .htaccess file) to redirect all traffic from one domain to another. This also keeps the query string in place so that the user isn't just dumped to the homepage.