The *netinstall.conf* file should have this format:
----
groupsUrl: <URLtoYAMLfile>
The URL must point to a YAML file. Here is a short example of how the YAML file should look.
- name: "Group name"
description: "Description of the group"
packages:
- lsb-release
- avahi
- grub
- name: "Second group name"
...
The file is composed of a list of entry, each describing one group. The keys *name*, *description* and *packages* are required.
Two more keys are supported, *hidden* (if true, do not show the group on the page) and *selected* (if true, display the group as selected). Both default to false if not present.
If both keys are set to true for the same group, you are basically creating a "default" group of packages which will always be installed in the user's system.