I wanted to understand how dos cloud-init, curtin and the ephemeral image work together. I’m trying to write the role of each in the MAAS architecture.
Cloud-init has two configuration sources:
Cloud provider-supplied metadata: this stage happens before the image installation. Is this where curtin goes? it’s the configuration defined in curtin that goes in this stage?
User-supply configuration runs after the machine has Deployed. Here it’s the files that the user can run when they deploy a machine correct?
Ephemeral images, use cloud-init to discover the node’s hardware (e.g., number of CPUs,RAM, disk, etc.) and send that information to the MAAS Region controller.
So ephemeral images also use cloud-init.
Curtin applies customization during operating system (OS) image installation. System parameterssuch as the type of kernel, disk partitioning, network configuration, swap memory configura-tion, among others, can be preconfigured in a preseed file that will automatically configureimages during the installation process
What I wanted to understand is the chronology of these events, what calls what and when.
And what are the differences between them.
Thanks for the help