Linux – Best way to merge MySQL databases and WordPress files in a cross-platform dev. environment

Check out Eric Hammond's article explaining how to use Elastic IP addresses even from within EC2. This method does NOT result in any bandwidth charges because resolving the Elastic IP address (by name) from within EC2 returns the Private IP address.

http://alestic.com/2009/06/ec2-elastic-ip-internal

For more options, I have an article examining a few alternatives:

http://shlomoswidler.com/2010/06/track-changes-to-your-dynamic-cloud-services-automatically.html

Generally speaking your testing environment should be entirely separate from your production environment -- This allows you to test things like software updates before rolling them out to production, so if they break stuff you can determine what and how to fix it without the time pressures associated with your live environment being down.

My suggestion for an ideal scenario would be to build a development environment that is an exact copy of your production environment - same releases of all software, same database contents, etc. This can be made publicly accessible, or locked away behind a firewall where all your developers & QA folks VPN in to do their work (which way you go depends heavily on your workflow and processes, but I personally like the VPN solution).

It's also often advantageous to build your development environment using something like VMWare, where you can snapshot the environment before making major changes.

You will also need a process in place for promoting your changes to production. If you have the time to invest in a solution like Puppet or radmind now it will make future deployments much easier (VMWare comes in handy here too -- You can test your deployment process on virtual machines and debug it so when it runs in production you know how it will behave).