PremiScale is a controller that brings autoscaling of virtual and physical infrastructure to local, self-hosted and private datacenters, with a particular focus on integrating with the Kubernetes cluster autoscaler.
PremiScale uses libvirt to connect to hosts and manage lifecycles of virtual machines. The Libvirt daemon provides a rich API for interacting with hypervisors, hosts and virtual machines.
The controller can be configured to run in two different modes, including kubernetes
(the default) and standalone
modes. In either configuration, the controller aims to start only relevant processes for both data collection and managing virtual machines. Users are required at this time to provide a list of hosts on which virtual machines can be created, in addition to a list of autoscaling groups, into which virtual machines the controller manages, are organized.
In standalone
mode (the default), the controller starts its own time series data collection process.
Starting the controller in kubernetes
mode starts relevant components of the controller that allow it to interface with the cluster autoscaler.
Note that, in this configuration, the controller does not require a time series database. State is still reconciled, but the time series signal comes from the cluster autoscaler instead.
The controller is configured in a couple ways, including its command line interface, environment variables (as indicated in the help text below), and through the required config file (all versions of which are documented here in this repository).
This project is intended to be deployed to Kubernetes, whether you intend to integrate with the cluster autoscaler or not.
See the Helm chart README for an overview of controller installation.