Chapter 1. Postinstallation configuration overview

After installing OpenShift Container Platform, a cluster administrator can configure and customize the following components:

  • Machine
  • Bare metal
  • Cluster
  • Node
  • Network
  • Storage
  • Users
  • Alerts and notifications

1.1. Post-installation configuration tasks

You can perform the post-installation configuration tasks to configure your environment to meet your need.

The following lists details these configurations:

  • Configure operating system features: The Machine Config Operator (MCO) manages MachineConfig objects. By using the MCO, you can configure nodes and custom resources.

  • Configure bare metal nodes: You can use the Bare Metal Operator (BMO) to manage bare metal hosts. The BMO can complete the following operations:

    • Inspects hardware details of the host and report them to the bare metal host.
    • Inspect firmware and configure BIOS settings.
    • Provision hosts with a desired image.
    • Clean disk contents for the host before or after provisioning the host.

  • Configure cluster features. You can modify the following features of an OpenShift Container Platform cluster:

    • Image registry
    • Networking configuration
    • Image build behavior
    • Identity provider
    • The etcd configuration
    • Machine set creation to handle the workloads
    • Cloud provider credential management

  • Configuring a private cluster: By default, the installation program provisions OpenShift Container Platform by using a publicly accessible DNS and endpoints. To make your cluster accessible only from within an internal network, configure the following components to make them private:

    • DNS
    • Ingress Controller
    • API server

  • Perform node operations: By default, OpenShift Container Platform uses Red Hat Enterprise Linux CoreOS (RHCOS) compute machines. You can perform the following node operations:

    • Add and remove compute machines.
    • Add and remove taints and tolerations.
    • Configure the maximum number of pods per node.
    • Enable Device Manager.

  • Configure network: After installing OpenShift Container Platform, you can configure the following components:

    • Ingress cluster traffic
    • Node port service range
    • Network policy
    • Enabling the cluster-wide proxy

  • Configure storage: By default, containers operate by using the ephemeral storage or transient local storage. The ephemeral storage has a lifetime limitation. To store the data for a long time, you must configure persistent storage. You can configure storage by using one of the following methods:

    • Dynamic provisioning: You can dynamically provision storage on demand by defining and creating storage classes that control different levels of storage, including storage access.
    • Static provisioning: You can use Kubernetes persistent volumes to make existing storage available to a cluster. Static provisioning can support various device configurations and mount options.
  • Configure users: OAuth access tokens allow users to authenticate themselves to the API. You can configure OAuth to perform the following tasks:
  • Specify an identity provider
  • Use role-based access control to define and supply permissions to users
  • Install an Operator from OperatorHub
  • Configuring alert notifications: By default, firing alerts are displayed on the Alerting UI of the web console. You can also configure OpenShift Container Platform to send alert notifications to external systems.