»Automatic OS Installs
If you are building from a brand-new and unconfigured operating system image, Packer will need you to perform the operating system install before it can connect to and configure your image using its provisioners. Most operating system distributions have a mechanism for performing the normally-interactive installation in an automated way. For Debian operating systems, this is done using a preseed file; for Windows, it's done using an Autounattend.xml. We have compiled some simple guides here for common operating system distributions.
These guides are meant to give you a quick introduction to how to use automated installation answer files in order to perfom those installs; we don't mean to be a comprehensive guide on each operating system, but we hope to give you enough context to be able to more easily find any further information you need.
Please use the left-hand navigation to find instructions for the operating system that is relevant to you.