Chapter 1. Overview of machine management
You can use machine management to flexibly work with underlying infrastructure like Amazon Web Services (AWS), Azure, Google Cloud Platform (GCP), OpenStack, Red Hat Virtualization (RHV), and vSphere to manage the OpenShift Container Platform cluster. You can control the cluster and perform auto-scaling, such as scaling up and down the cluster based on specific workload policies.
The OpenShift Container Platform cluster can horizontally scale up and down when the load increases or decreases. It is important to have a cluster that adapts to changing workloads.
Machine management is implemented as a Custom Resource Definition(CRD). A CRD object defines a new unique object Kind in the cluster and enables the Kubernetes API server to handle the object’s entire lifecycle.
The Machine API Operator provisions the following resources:
- MachineSet
- Machine
- Cluster Autoscaler
- Machine Autoscaler
- Machine Health Checks
What you can do with machine sets
As a cluster administrator you can:
Create a machine set on:
- Manually scale a machine set by adding or removing a machine from the machine set.
- Modify a machine set through the MachineSet YAML configuration file.
- Delete a machine.
- Create infrastructure machine sets.
- Configure and deploy a machine health check to automatically fix damaged machines in a machine pool.
Autoscaler
Autoscale your cluster to ensure flexibility to changing workloads. To autoscale your OpenShift Container Platform cluster, you must first deploy a cluster autoscaler, and then deploy a machine autoscaler for each machine set. The cluster autoscaler increases and decreases the size of the cluster based on deployment needs. The machine autoscaler adjusts the number of machines in the machine sets that you deploy in your OpenShift Container Platform cluster.
User-provisioned infrastructure
User-provisioned infrastructure is an environment where you can deploy infrastructure such as compute, network, and storage resources that host the OpenShift Container Platform. You can add compute machines to a cluster on user-provisioned infrastructure either as part of or after the installation process.
What you can do with RHEL compute machines
As a cluster administrator, you can:
- Add Red Hat Enterprise Linux (RHEL) compute machines, also known as worker machines, to a user-provisioned infrastructure cluster or an installation-provisioned infrastructure cluster.
- Add more Red Hat Enterprise Linux (RHEL) compute machines to an existing cluster.
