Red Hat OpenShift agent-based installer support for Oracle Cloud Infrastructure

In the ever-evolving landscape of cloud computing, the efficient deployment and management of containerized applications are paramount. With the integration of Red Hat OpenShift on Oracle Cloud Infrastructure (OCI), a powerful and adaptable solution for orchestrating OpenShift clusters on OCI is now at your fingertips. This article delves deep into this exciting development.

Embracing versatility with Red Hat OpenShift 4.14

Starting from OpenShift 4.14, users are presented with two distinct installation methods. You can now install an OpenShift cluster on Oracle Cloud Infrastructure through either of the following approaches:

1. SaaS-based assisted installer

For those who appreciate a user-friendly Software-as-a-Service (SaaS)-based installation experience, OpenShift offers the assisted installer. This installer provides an intuitive, graphical user interface-driven approach for deploying OpenShift clusters. It simplifies the installation process, making it easier even for users who may not be deeply familiar with command line interfaces (CLIs). The assisted installer is accessible via the Red Hat Hybrid Cloud Console and is well suited for environments with internet connectivity, enabling your cluster to connect to the broader online ecosystem.

2. CLI-based agent-based installer

Important: Using the Agent-based Install to install an OpenShift cluster on OCI is a Developer Preview feature. For more information see Developer and Technology Previews: How they compare.

The agent-based installation method introduces flexibility that lets users boot their on-premises servers in the manner they choose. It combines the user-friendliness of the assisted installation service with offline capabilities, including deployment in air-gapped environments. This method is a subcommand of the OpenShift installer. It generates a bootable ISO image containing all the necessary information to deploy an OpenShift cluster, complete with an available release image.

The configuration for agent-based installation follows the same format as the installer-provisioned infrastructure and user-provisioned infrastructure installation methods. Moreover, the agent-based installer can optionally generate or accept Zero-Touch Provisioning (ZTP) custom resources, facilitating the provisioning of new edge sites with declarative configurations for bare-metal equipment.

Agent-based installer features

You can leverage the benefits of the assisted installer hosted service as an OpenShift user, even in disconnected environments. The agent-based installation involves a bootable ISO containing the assisted discovery agent and the assisted service. While both components are essential for cluster installation, the latter runs on only one of the hosts.

The openshift-install agent create image subcommand generates an ephemeral ISO based on user-provided inputs through manifests such as install-config.yaml and agent-config.yaml. Alternatively, users can opt for ZTP manifests for configuring bare-metal equipment.

Interested? Request access to Red Hat OpenShift on Oracle Cloud Infrastructure in Developer Preview.

About Oracle Cloud Infrastructure (OCI)

Oracle Cloud Infrastructure offers a comprehensive suite of cloud services, enabling users to develop and run a wide range of applications in a highly available, high-performance environment. OCI’s distributed cloud gives users greater control over data residency, locality and authority, even in multicloud scenarios. 

OCI features:

• Multicloud capabilities, allowing customers to choose the best cloud provider for their applications and databases
• Hybrid cloud options
• Public cloud with 45 cloud regions across 23 countries, including an EU Sovereign Cloud, addressing data residency and sovereignty requirements
• Dedicated cloud regions and Oracle Alloy for tailored cloud services and experiences

Red Hat OpenShift with Oracle Cloud Infrastructure

OpenShift is now supported and certified to run on OCI with the release of Red Hat OpenShift 4.14. This support extends to customer-managed installations using certified configurations of Red Hat OpenShift Platform Plus, Red Hat OpenShift Container Platform and Red Hat OpenShift Kubernetes Engine, running on Oracle Cloud Infrastructure compute virtual machines and bare metal instances.

Overview of agent-based installer support for OCI

In the latest OpenShift 4.14 release, the agent-based installer extends its support to a new platform type: external for the Oracle Cloud Infrastructure provider. Here are the key requirements for utilizing this support:

• Minimum OpenShift version required: OpenShift 4.14
• When using an external platform, the platformName can only be set to oci.
• When using an external platform, the cloudControllerManager must be set to External.
• The agent-based installer can generate a minimal ISO with or without explicitly creating the rootfs.img file, which is dynamically loaded into memory during the boot process.
• All cluster topologies are supported, including Single Node OpenShift (SNO), Highly Available (HA), and Compact, along with the connected, disconnected, and dual-stack networking.

How to generate the agent ISO

1. Prepare agent-config.yaml and install-config.yaml files.
2. Prepare CCM and CSI manifest YAML files.
3. Get the latest openshift-install binary.
4. Run ./openshift-install agent create image  — —log-level debug to generate the ISO image.

Wrap up

This article explored the integration of Red Hat OpenShift’s agent-based installer with Oracle Cloud Infrastructure, opening up new possibilities for deploying and managing containerized applications efficiently.