Theory of Air-gapped packages

Kubean CI builds offline assets to install Kubernetes in air-gapped environment.

NOTE: About usage for the offline assets, please refer to offline.md

This chapter explains the theory how the air-gapped packages come from.

• Assets: Github Releases
• Major contents:

Asset	Description
files-*.tar.gz	The binaries required in Kubespray installation: example : kubeadm, runc
images-*.tar.gz	The k8s cluster images as well as CNI images
os-pkgs-${linux_distribution}-${tag}.tar.gz	deb/rpm required during k8s installion

How to build the assets

1. Images & binaries

   As stated in Kubespray offline deployment guide, Kubespray already provides scripts to generate images and binaries list. (Thanks to great Kubespray! )

   With help of Kubespray script to generate binaries & images list, then we can use manage-offline-files.sh to download those binaries and images. At last, Kubean provides an call-offline-build.yaml(Github Action scripts) to make them together.

2. os-packages (deb/rpm)

   During the k8s installation, a few packages could not be installed as binaries, so we have to install them via deb/rpm. The os packages list defines what packages will be involved.

   Github Action will build packages in different OS (as Qemu) via dnf/apt to download and archive RPM/DEB packages.

3. CI process

   The offline assets are generated/managed by Github Action scripts.