OpenShift Prerequisites

OpenShift Prerequisites

Before installing OpenShift, ensure the following prerequisites are met for your environment.

1. Red Hat Account

A Red Hat account is required to download the installer, access the pull secret, and manage subscriptions.
👉 Create a Red Hat Account

2. OpenShift Installer

Download the OpenShift installer appropriate for your target environment (bare metal, VMware, AWS, Azure, or GCP).
👉 Download the Installer

3. Pull Secret

The pull secret is required to access Red Hat’s container registries during installation.
👉 Download Pull Secret

4. DNS and Networking

  • Ensure DNS resolution is properly configured for the cluster.
  • Required DNS records:
    • api.<cluster_name>.<base_domain> → Load balancer or bootstrap node
    • *.apps.<cluster_name>.<base_domain> → Application load balancer
  • Configure reverse DNS lookup for all nodes.
  • Ensure required firewall ports are open (API, ingress, node-to-node communication).
    👉 OpenShift Networking Requirements

5. Infrastructure (VMs or Bare Metal)

Provision infrastructure based on your target platform:

Bare Metal

  • Minimum of 3 master nodes (control plane)
  • Worker nodes (based on workload requirements)
  • Hardware (per node):
    • Master: 4 vCPU, 16 GB RAM, 120 GB disk
    • Worker: 4 vCPU, 8 GB RAM, 120 GB disk

VMware vSphere

  • vCenter access with admin privileges
  • Pre-created VM templates or ability to create VMs
  • Shared datastore and networking

Public Clouds (AWS, Azure, GCP)

  • Proper IAM roles and permissions
  • Region and VPC/subnet prepared
  • Load balancers enabled
  • Storage services (EBS, Azure Disk, GCP Persistent Disk) available

6. Cloud CLI Tools

AWS CLI

👉 Download AWS CLI

Azure CLI

👉 Download Azure CLI

GCP SDK

👉 Download Google Cloud SDK

VMware CLI Tools

  • ovftool for importing templates
  • vSphere client access

7. Certificates and Security

  • Configure TLS certificates (self-signed or custom CA if required).
  • Ensure SSH key pair is generated for cluster node access.
    👉 Generate SSH Key

8. Storage Requirements

  • Infrastructure storage for etcd and control plane.
  • Persistent storage for applications (NFS, Ceph, GlusterFS, EBS, Azure Disk, GCP PD, VMware vSAN).
    👉 Storage Requirements

9. Operating System Requirements

  • Supported OS for nodes:
    • Red Hat Enterprise Linux CoreOS (RHCOS) – default
    • Red Hat Enterprise Linux (RHEL) with prerequisites installed
  • Ensure subscription is attached for RHEL nodes.
  • oc CLI (OpenShift client) 👉 Download OC CLI
  • kubectl CLI (for Kubernetes-level operations)
  • Infrastructure automation tools (Terraform, Ansible) for IaC deployments

✅ With these prerequisites completed, you are ready to begin the OpenShift installation on your target platform.