First, you will have to disable the EC2 version of MediaCache that is built-in and supports the Wowza EC2 application named “vods3”, which is designed to use S3. To do that you have to remove this ServerListener from /conf/Server.xml:
Then you can configured the regular MediaCache package as normal.
To preserve that configuration for re-use, you can use a startup package. Which are detailed in the Wowza EC2 User Guide. It’s basically a set of files that mirror the Wowza configuration, or the parts that you want to be customized, and is zipped up and used when you launch an instance to automatically configure the instance. In this case you would include the modified Server.xml, and your application configurations and the mediacache jar. There is a size limit, so if the jar puts you over that you will have to use a Download tag in the startup.xml in the startup package. Details are in the Wowa EC2 guide.