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 OKD cluster. You can control the cluster and perform auto-scaling, such as scaling up and down the cluster based on specific workload policies.
The OKD 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
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.
Configure and deploy a machine health check to automatically fix damaged machines in a machine pool.
Autoscale your cluster to ensure flexibility to changing workloads. To autoscale your OKD 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 OKD cluster.
User-provisioned infrastructure is an environment where you can deploy infrastructure such as compute, network, and storage resources that host the OKD. You can add compute machines to a cluster on user-provisioned infrastructure either as part of or after the installation process.
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.