Once Krieger and his engineers were ready to actually move software and data from place to place, they turned to an increasingly popular tool called Chef. This is a way of writing automated “recipes” for loading and configuring digital stuff on a vast array of machines. They wrote recipes, for instance, that could automatically load the appropriate software onto machines running in the Amazon VPC. Then they used similar recipes to load much the same software on machines inside the Facebook data center. It built recipes for installing software on each flavor of Instagram database server, another for configuring what are called caching servers, which are used to more quickly serve up particularly popular photos, and so on.

How Facebook Moved 20 Billion Instagram Photos Without You Noticing | Enterprise | WIRED