Understanding cloud-init architecture

Cloud-init works with the concept of boot stages because it needs fine and granular control over what happens to the system during boot. The prerequisite for cloud-init would, of course, be a cloud-init image. From the documentation available at https://cloudinit.readthedocs.io, we can learn that there are five stages to a cloud-init boot:

• The generator is the first one, and the simplest one: it will determine whether we are even trying to run cloud-init, and based on that, whether it should enable or disable the processing of data files. Cloud-init will not run if there are kernel command-line directives to disable it, or if a file called /etc/cloud/cloud-init.diabled exists. For more information on this and all the other things in this chapter, please read the documentation (start at https://cloudinit.readthedocs.io/en/latest/topics/boot.html) since it contains much more detail about switches and different options that cloud-init supports...