ONCE YOU HAVE AN IDEA OF HOW MUCH CAPACITY YOU'LL NEED FOR FUTURE GROWTH AND HAVE PURCHASED the hardware, you'll need to physically install it and deploy it into production.
Historically, deployment has been viewed as a headache. Installing the operating system and application software, making sure all of the right settings are in place, and loading your website's data—all these tedious steps must be done in order to integrate new hardware that's fresh out of the crate. Fortunately, the pain of repeating these steps over and over has inspired an entire category of software: automated installation and configuration tools.
Although various automatic installation and configuration tools differ in their implementation and execution, most of them share the same design philosophy. Just as with monitoring and metric-collection tools, many of these concepts and designs originated in the high-performance computing (HPC) field. Because HPC and web operations have similarities in their infrastructure, the web operations community has adopted many of these tools and approaches.
The time needed to acquire, install, and provision new hardware must be factored into your calculations as you determine when you're going to run out of capacity. If your capacity will be exhausted in six weeks, and it takes you three weeks to add new hardware, you only have three weeks of breathing room. Automated deployment ...