How it works...

To prepare the vSphere environment for auto deploy, we perform the following steps:

Create a host profile from a reference host, a host profile conserves the efforts in replicating much of the commonly used configuration parameters typically used in the environment. There is a natural cohesion of the feature with auto deploy.
Create a software depot to store image profiles, typically more than one depending on the environment needs.
Create deploy rules to match specific hosts to specific images.

In a complex and large infrastructure, there could be heterogeneous versions of products in terms of software, hardware, drivers, and so on. Hence, the auto deploy feature enables the creation of multiple image profiles and a set of rules through which targeted deployments could be performed. In addition, auto deploy use cases stretch beyond the typical deployments to managing the life cycle of the hosts, by accommodating updates/upgrades as well.

There are two primary modes of auto deploy:

Stateless caching: On every reboot, the host continues to use vSphere auto deploy infrastructure to retrieve its image. However, if auto deploy server is inaccessible, it falls back to a cached image.
Stateful install: In this mode, an installation is performed on the disk and subsequent reboots would boot off the disk. This setting is controlled through the host profile setting system cache configuration.