Warning
The Immutable Installer is in alpha status and is under active development. Its configuration and behavior can change between releases.
Immutable Installer is a Kubernetes installer for the SIGHUP Distribution (SD). The installer has a set of Ansible roles that create a Kubernetes cluster on Flatcar Container Linux machines.
If you are new to SD, refer to the official documentation to get started.
The installer uses open source tools to create a Kubernetes cluster on Flatcar Container Linux machines. furyctl
bootstraps and configures these machines with Ignition and with the system extensions (sysext) from the
installer-immutable-sysext repository.
These roles are part of the SIGHUP Distribution Immutable Installer:
| Role | Description |
|---|---|
| containerd | Ansible role to configure containerd as the container runtime |
| etcd | Ansible role to configure etcd on the control-plane nodes or on separate nodes |
| haproxy | Ansible role to configure HAProxy as the load balancer for the API server |
| keepalived | Ansible role to configure keepalived for a virtual IP address that the nodes share (HA) |
| kube-control-plane | Ansible role to configure the control-plane nodes |
| kube-worker | Ansible role to configure the worker nodes and to join them to the cluster |
| node-maintenance | Task-file library for upgrades: it cordons, drains, and then uncordons a node |
| os-upgrade | Task-file library for upgrades: it does the Flatcar A/B OS update (stage, reboot, mark good) |
| sysctl | Ansible role to configure the kernel parameters on the machines |
| sysext | Helper role to align the binary system extensions to their target versions |
| upgrade-gates | Task-file library for upgrades: read-only checks of the cluster health and the infrastructure |
Click on each role to read its full documentation.
Refer to the compatibility matrix for the versions that this installer supports.
To create or to upgrade a Kubernetes cluster with this installer, use furyctl. furyctl is our companion
CLI tool that manages the full life cycle of SD clusters.
The Immutable provider automates this installer completely. SIGHUP does not support stand-alone use of the installer.
If you use it stand-alone, you accept the risk.
The Immutable Installation Guide shows how the Immutable kind installs a cluster, on bare-metal
machines or on virtual machines. The guide is an index: it shows the boot decision and the flow that all the cases have in
common. It also links to one document for each case: DHCP and PXE, iPXE ISO, deploy DHCP, and manual OS ISO. In the guide,
key terms link to their official documentation.
In case you experience any problems with the installer, please open a new issue.
This module is open-source and it's released under the following LICENSE.