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Chapter 3. Customizing your environment using Operators and Operator Bundles

You can customize the OpenShift Container Platform deployment by selecting one or more Operators or Operator bundles during the installation.

3.1. Customizing with Operators

Operators are used to package, deploy, and manage services and applications. Before starting the installation, familiarize yourself with the Assisted Installer Operators, including their prerequisites and limitations. If you require advanced options, install the Operators after you have installed the cluster.

Important

The additional requirements specified below apply to each Operator individually. If you select more than one Operator, or if the Assisted Installer automatically selects an Operator due to dependencies, the total required resources is the sum of the resource requirements for each Operator.

Additional resources

3.1.1. OpenShift Virtualization Operator

You can deploy OpenShift Virtualization to perform the following tasks:

  • Create and manage Linux and Windows virtual machines (VMs).
  • Run pod and VM workloads alongside each other in a cluster.
  • Connect to VMs through a variety of consoles and CLI tools.
  • Import and clone existing VMs.
  • Manage network interface controllers and storage drives attached to VMs.
  • Live migrate VMs between nodes.

The OpenShift Virtualization Operator requires backend storage and might automatically activate a storage Operator in the background, according to the following criteria:

  • None - If the CPU architecture is ARM64, no storage Operator is activated.
  • LVM Storage - For single-node OpenShift clusters on any other CPU architecture deploying OpenShift Container Platform 4.12 or higher.
  • Local Storage Operator (LSO) - For all other deployments.

Prerequisites

  • Requires enabled CPU virtualization support in the firmware on all nodes.
  • Requires an additional 360 MiB of memory and 2 CPU cores for each compute (worker) node.
  • Requires an additional 150 MiB of memory and 4 CPU cores for each control plane node.

  • Requires Red Hat OpenShift Data Foundation (recommended for creating additional on-premise clusters), Logical Volume Manager Storage, or another persistent storage service.

    Important

    Deploying OpenShift Virtualization without Red Hat OpenShift Data Foundation results in the following scenarios:

    • Multi-node cluster: No storage is configured. You must configure storage after the OpenShift Data Foundation configuration.
    • Single-node OpenShift: Logical Volume Manager Storage (LVM Storage) is installed.

    You must review the prerequisites to ensure that your environment has sufficient additional resources for OpenShift Virtualization.

  • OpenShift Virtualization is not supported on the following platforms: Nutanix, vSphere.
  • OpenShift Virtualization is not compatible with the following CPU architectures: S390X, PPC64LE.
  • OpenShift Virtualization is supported from OpenShift Container Platform 4:14 and later.

Procedure

Additional resources

3.1.2. Migration Toolkit for Virtualization Operator

The Migration Toolkit for Virtualization Operator allows you to migrate virtual machines at scale to a local or remote Red Hat OpenShift Virtualization cluster. You can perform the migration from any of the following source providers:

  • VMware vSphere
  • Red Hat Virtualization (RHV)
  • Red Hat OpenShift Virtualization
  • OpenStack

When you select the Migration Toolkit for Virtualization Operator, the Assisted Installer automatically activates the OpenShift Virtualization Operator. For a Single-node OpenShift installation, the Assisted Installer also activates the LVM Storage Operator.

You can install the Migration Toolkit for Virtualization Operator on OpenShift Container Platform using the Assisted Installer, either independently or as part of the OpenShift Virtualization Operator bundle.

Prerequisites

  • Requires OpenShift Container Platform version 4.14 or later.
  • Requires an x86_64 CPU architecture.
  • Requires an additional 1024 MiB of memory and 1 CPU core for each control plane node and worker node.
  • Requires the additional resources specified for the OpenShift Virtualization Operator, installed together with OpenShift Virtualization. For details, see the prerequisites in the OpenShift Virtualization Operator section.

Procedure

Post-installation steps

After completing the installation, the Migration menu appears in the navigation pane of the Red Hat OpenShift web console.

The Migration menu provides access to the Migration Toolkit for Virtualization. Use the toolkit to create and execute a migration plan with the relevant source and destination providers.

For details, see either of the following chapters in the Migration Toolkit for Virtualization Guide:

Additional resources

3.1.3. Multicluster engine for Kubernetes Operator

You can deploy the multicluster engine for Kubernetes to perform the following tasks in a large, multi-cluster environment:

  • Provision and manage additional Kubernetes clusters from your initial cluster.
  • Use hosted control planes to reduce management costs and optimize cluster deployment by decoupling the control and data planes.
  • Use GitOps Zero Touch Provisioning to manage remote edge sites at scale.

You can deploy the multicluster engine with OpenShift Data Foundation on all OpenShift Container Platform clusters.

Prerequisites

  • Requires an additional 16384 MiB of memory and 4 CPU cores for each compute (worker) node.
  • Requires an additional 16384 MiB of memory and 4 CPU cores for each control plane node.

  • Requires OpenShift Data Foundation (recommended for creating additional on-premise clusters), LVM Storage, or another persistent storage service.

    Important

    Deploying multicluster engine without OpenShift Data Foundation results in the following scenarios:

    • Multi-node cluster: No storage is configured. You must configure storage after the installation process.
    • Single-node OpenShift: LVM Storage is installed.

    You must review the prerequisites to ensure that your environment has sufficient additional resources for the multicluster engine.

Procedure

Additional resources

3.1.4. Logical Volume Manager Storage Operator

You can use LVM Storage to dynamically provision block storage on a limited resources cluster.

Prerequisites

  • Requires at least 1 non-boot drive per host.
  • Requires 100 MiB of additional RAM.
  • Requires 1 additional CPU core for each non-boot drive.

Procedure

Additional resources

3.1.5. Red Hat OpenShift Data Foundation Operator

You can use OpenShift Data Foundation for file, block, and object storage. This storage option is recommended for all OpenShift Container Platform clusters. OpenShift Data Foundation requires a separate subscription.

Prerequisites

  • There are at least 3 compute (workers) nodes, each with 19 additional GiB of memory and 8 additional CPU cores.
  • There are at least 2 drives per compute node. For each drive, there is an additional 5 GB of RAM.
  • You comply to the additional requirements specified here: Planning your deployment.
Note

You cannot install the OpenShift Data Foundation Operator on Oracle third-party platforms such as Oracle® Cloud Infrastructure or Oracle® Compute Cloud@Customer.

Procedure

Additional resources

3.1.6. OpenShift Artificial Intelligence (AI) Operator

Red Hat® OpenShift® Artificial Intelligence (AI) is a flexible, scalable artificial intelligence (AI) and machine learning (ML) platform that enables enterprises to create and deliver AI-enabled applications at scale across hybrid cloud environments. Red Hat® OpenShift® AI enables the following functionality:

  • Data acquisition and preparation.
  • Model training and fine-tuning.
  • Model serving and model monitoring.
  • Hardware acceleration.

The OpenShift AI Operator enables you to install Red Hat® OpenShift® AI on your OpenShift Container Platform cluster. From OpenShift Container Platform version 4.17 and later, you can use the Assisted Installer to deploy the OpenShift AI Operator to your cluster during the installation.

For the developer preview, installing the OpenShift AI Operator automatically installs the following Operators:

Important

The integration of the OpenShift AI Operator into the Assisted Installer is a Developer Preview feature only. Developer Preview features are not supported by Red Hat in any way and are not functionally complete or production-ready. Do not use Developer Preview features for production or business-critical workloads. Developer Preview features provide early access to upcoming product features in advance of their possible inclusion in a Red Hat product offering, enabling customers to test functionality and provide feedback during the development process. These features might not have any documentation, are subject to change or removal at any time, and testing is limited. Red Hat might provide ways to submit feedback on Developer Preview features without an associated SLA.

Prerequisites

  • You are installing OpenShift Container Platform version 4.17 or later.

  • You meet the following miminum requirements for the OpenShift AI Operator:

    • Requires at least 2 compute (worker) nodes, each with 32 additional GiB of memory and 8 additional CPU cores.
    • Requires at least 1 supported GPU. Currently only NVIDIA GPUs are supported.
    • Nodes with NVIDIA GPUs installed must have Secure Boot disabled.
  • You meet the additional minimum requirements specified for the dependent Red Hat OpenShift Data Foundation Operator.
  • You meet the additional requirements specified here: Requirements for OpenShift AI.
Note

You cannot install the OpenShift AI Operator on Oracle third-party platforms such as Oracle® Cloud Infrastructure or Oracle® Compute Cloud@Customer.

Procedure

Additional resources

3.1.7. OpenShift sandboxed containers Operator

The OpenShift sandboxed containers Operator provides an additional virtual machine (VM) isolation layer for pods, which manages the installation, configuration, and updating of sandboxed containers runtime (Kata containers) on Red Hat OpenShift clusters. You can install the sandboxed containers runtime in an Red Hat OpenShift cluster by using the Assisted Installer.

Important

The integration of the OpenShift sandboxed containers Operator into the Assisted Installer is a Technology Preview feature only. Technology Preview features are not supported with Red Hat production service level agreements (SLAs) and might not be functionally complete. Red Hat does not recommend using them in production. These features provide early access to upcoming product features, enabling customers to test functionality and provide feedback during the development process.

For more information about the support scope of Red Hat Technology Preview features, see https://access.redhat.com/support/offerings/techpreview/.

Prerequisites

The required functionality for the OpenShift Container Platform is supported by two main components:

  • OpenShift Container Platform: Use OpenShift Container Platform version 4.17 or later to install OpenShift sandboxed containers on an Red Hat OpenShift cluster using the Assisted Installer. To learn more about the requirements for OpenShift sandboxed containers, see OpenShift sandboxed containers resource requirements.

  • Kata runtime: This includes Red Hat Enterprise Linux CoreOS (RHCOS) and updates with every OpenShift Container Platform release. The Operator depends on the features that come with the RHCOS host and the environment it runs in.

    Note

    You must install Red Hat Enterprise Linux CoreOS (RHCOS) on the worker nodes. RHEL nodes are not supported.

Procedure

Additional resources

3.1.8. Kubernetes NMState Operator

NMState is a declarative NetworkManager API designed for configuring network settings using YAML or JSON-based instructions. The Kubernetes NMState Operator allows you to configure network interface types, DNS, and routing on the cluster nodes using NMState.

You can install the Kubernetes NMState Operator on OpenShift Container Platform using the Assisted Installer, either separately or as part of the OpenShift Virtualization Operator bundle. Installing the Kubernetes NMState Operator with the Assisted Installer automatically creates a kubernetes-nmstate instance, which deploys the NMState State Controller as a daemon set across all of the cluster nodes. The daemons on the cluster nodes periodically report on the state of each node’s network interfaces to the API server.

Prerequisites

  • Supports OpenShift Container Platform 4.12 or later.
  • Requires an x86_64 CPU architecture.
  • Cannot be installed on the Nutanix and Oracle Cloud Infrastructure platforms.

Procedure

Additional resources

3.1.9. Fence Agents Remediation Operator

You can use Fence Agents Remediation Operator to automatically recover unhealthy nodes on environments with a traditional API end-point. When a node in the OpenShift Container Platform cluster becomes unhealthy or unresponsive, the Fence Agents Remediation Operator utilizes an external set of fencing agents to isolate it from the rest of the cluster. A fencing agent then resets the unhealthy node in an attempt to resolve transient hardware or software issues. Before or during the reboot process, the Fence Agents Remediation Operator safely moves workloads (pods) running on the unhealthy node to other healthy nodes in the cluster.

You can only install the Fence Agents Remediation Operator as part of the Virtualization Operator bundle.

Important

The integration of the Fence Agents Remediation Operator into the Assisted Installer is a Developer Preview feature only. Developer Preview features are not supported by Red Hat in any way and are not functionally complete or production-ready. Do not use Developer Preview features for production or business-critical workloads. Developer Preview features provide early access to upcoming product features in advance of their possible inclusion in a Red Hat product offering, enabling customers to test functionality and provide feedback during the development process. These features might not have any documentation, are subject to change or removal at any time, and testing is limited. Red Hat might provide ways to submit feedback on Developer Preview features without an associated SLA.

Prerequisites

Procedure

Post-installation steps

  • Create the FenceAgentsRemediationTemplate custom resource to define the required fencing agents and remediation parameters. For details, see Configuring the Fence Agents Remediation Operator.
  • Configure the NodeHealthCheck custom resource by either replacing the default SelfNodeRemediation provider with FenceAgentsRemediation or by adding FenceAgentsRemediation as an additional remediation provider.

Additional resources

3.1.10. Kube Descheduler Operator

The Kube Descheduler Operator is a Kubernetes operator that automates the deployment, configuration, and management of the Kubernetes Descheduler within a cluster. You can use the Kube Descheduler Operator to evict pods (workloads) based on specific strategies, so that the pods can be rescheduled onto more appropriate nodes.

You can benefit from descheduling running pods in situations such as the following:

  • Nodes are underutilized or overutilized.
  • Pods and node affinity requirements, such as taints or labels, have changed and the original scheduling decisions are no longer appropriate for certain nodes.
  • Node failure requires pods to be moved.
  • New nodes are added to clusters.
  • Pods have been restarted excessively.

You can only install the Kube Descheduler Operator as part of the Virtualization Operator bundle.

Important

The integration of the Kube Descheduler Operator into the Assisted Installer is a Developer Preview feature only. Developer Preview features are not supported by Red Hat in any way and are not functionally complete or production-ready. Do not use Developer Preview features for production or business-critical workloads. Developer Preview features provide early access to upcoming product features in advance of their possible inclusion in a Red Hat product offering, enabling customers to test functionality and provide feedback during the development process. These features might not have any documentation, are subject to change or removal at any time, and testing is limited. Red Hat might provide ways to submit feedback on Developer Preview features without an associated SLA.

Prerequisites

Procedure

Additional resources

3.1.11. Local Storage Operator

The Local Storage Operator (LSO) enables the provisioning of persistent storage through local volumes. Local persistent volumes provide access to local storage devices, such as drives or partitions, by using the standard persistent volume claim interface.

You can perform the following actions using Local Storage Operator (LSO):

  • Assign the storage devices to the storage classes without modifying the device configuration.
  • Statically provision PVs and storage classes by configuring the LocalVolume custom resource (CR).
  • Create workloads and PVCs while being aware of the underlying storage topology.

Selecting the OpenShift Virtualization Operator, either independently or as part of the Virtualization bundle, automatically activates Local Storage Operator (LSO) in the background.

Prerequisites

Procedure

Additional resources

3.1.12. Node Health Check Operator

The Node Health Check Operator monitors node conditions based on a defined set of criteria to assess their health status. When detecting an issue, the Operator delegates remediation tasks to the appropriate remediation provider to remediate the unhealthy nodes. The Assisted Installer supports the following remediation providers:

The Self Node Remediation Operator is the default remediation provider for the Node Health Check Operator. The Assisted Installer always deploys these two Operators interdependently.

You can only install the Node Health Check Operator as part the Virtualization Operator bundle.

Important

The integration of the Node Health Check Operator into the Assisted Installer is a Developer Preview feature only. Developer Preview features are not supported by Red Hat in any way and are not functionally complete or production-ready. Do not use Developer Preview features for production or business-critical workloads. Developer Preview features provide early access to upcoming product features in advance of their possible inclusion in a Red Hat product offering, enabling customers to test functionality and provide feedback during the development process. These features might not have any documentation, are subject to change or removal at any time, and testing is limited. Red Hat might provide ways to submit feedback on Developer Preview features without an associated SLA.

Prerequisites

Procedure

Additional resources

3.1.13. Node Maintenance Operator

The Node Maintenance Operator facilitates planned maintenance by placing nodes into maintenance mode.

The Node Maintenance Operator watches for new or deleted NodeMaintenance custom resources (CRs). When it detects a new NodeMaintenance CR, it prevents new workloads from being scheduled on that node, and cordons off the node from the rest of the cluster. The Operator then evicts all pods that can be evicted from the node. When the administrator deletes the NodeMaintenance CR associated with the node, maintenance ends and the Operator makes the node available for new workloads.

You can only install the Node Maintenance Operator as part of the Virtualization Operator bundle.

Important

The integration of the Node Maintenance Operator into the Assisted Installer is a Developer Preview feature only. Developer Preview features are not supported by Red Hat in any way and are not functionally complete or production-ready. Do not use Developer Preview features for production or business-critical workloads. Developer Preview features provide early access to upcoming product features in advance of their possible inclusion in a Red Hat product offering, enabling customers to test functionality and provide feedback during the development process. These features might not have any documentation, are subject to change or removal at any time, and testing is limited. Red Hat might provide ways to submit feedback on Developer Preview features without an associated SLA.

Prerequisites

Procedure

Additional resources

3.1.14. Self Node Remediation Operator

You can use the Self Node Remediation Operator to automatically reboot unhealthy nodes. This remediation strategy minimizes downtime for stateful applications and ReadWriteOnce (RWO) volumes, and restores compute capacity if transient failures occur.

The Self Node Remediation Operator is the default remediation provider for the Node Health Check Operator. The Assisted Installer always deploys the two Operators interdependently.

You can only install the Self Node Remediation Operator as part of the Virtualization Operator bundle.

Important

The integration of the Self Node Remediation Operator into the Assisted Installer is a Developer Preview feature only. Developer Preview features are not supported by Red Hat in any way and are not functionally complete or production-ready. Do not use Developer Preview features for production or business-critical workloads. Developer Preview features provide early access to upcoming product features in advance of their possible inclusion in a Red Hat product offering, enabling customers to test functionality and provide feedback during the development process. These features might not have any documentation, are subject to change or removal at any time, and testing is limited. Red Hat might provide ways to submit feedback on Developer Preview features without an associated SLA.

Prerequisites

Procedure

Additional resources

3.2. Customizing with Operator Bundles

An Operator bundle is a recommended packaging format that combines related Operators to deliver a comprehensive set of capabilities. By selecting a bundle, administrators can extend functionality beyond that of a single Operator.

This approach makes the Assisted Installer more opinionated, offering an optimized platform for each selected bundle. It reduces the adoption barrier and minimizes the expertise required for customers to quickly access essential features. Additionally, it establishes a single, well-tested, and widely recognized path for platform deployments.

Meanwhile, individual Operators remain independent and free of unnecessary dependencies, ensuring a lightweight and flexible solution for small or specialized deployments, such as on single-node OpenShift.

When an administrator specifies an Operator bundle, the Assisted Installer automatically provisions the associated Operators included in the bundle. These Operators are predefined and cannot be deselected, ensuring consistency. Administrators can modify the selection after the installation has completed.

Additional resources

3.2.1. Virtualization Operator bundle

Virtualization lets you create multiple simulated environments or resources from a single, physical hardware system. The Virtualization Operator bundle provides a recommended and proven path for virtualization platform deployments, minimizing obstacles. The solution supports the addition of nodes and Day-2 administrative operations.

The Virtualization Operator bundle prompts the Assisted Installer to install the following Operators together:

Important

The Virtualization Operator bundle is a Developer Preview feature only. Developer Preview features are not supported by Red Hat in any way and are not functionally complete or production-ready. Do not use Developer Preview features for production or business-critical workloads. Developer Preview features provide early access to upcoming product features in advance of their possible inclusion in a Red Hat product offering, enabling customers to test functionality and provide feedback during the development process. These features might not have any documentation, are subject to change or removal at any time, and testing is limited. Red Hat might provide ways to submit feedback on Developer Preview features without an associated SLA.

Prerequisites

  • You are installing OpenShift Container Platform version 4.14 or later.
  • There is enabled CPU virtualization support in BIOS (Intel-VT/AMD-V) on all nodes.
  • Each control plane (master) node has an an additional 1024 MiB of memory and 3 CPU cores.
  • Each compute (worker) node has an additional 1024 MiB of memory and 5 CPU cores.
  • You have included the additional resources required to support the selected storage Operator.
  • You are installing a cluster of three or more nodes. The Virtualization Operator bundle is not available on single-node OpenShift.

Procedure

Additional resources

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