OpenShift v3 v4 differences

OpenShift, a Kubernetes-based container platform, has undergone significant changes from version 3 (v3) to version 4 (v4). Here are some of the key differences:

Architecture and Installation

1. Installer Types:
   • v3: Uses Ansible playbooks for installation.
   • v4: Introduces a new installer known as the OpenShift Installer, which simplifies setup and offers IPI (Installer Provisioned Infrastructure) and UPI (User Provisioned Infrastructure) methods.
2. CoreOS Integration:
   • v3: Uses RHEL (Red Hat Enterprise Linux) as the base operating system for nodes.
   • v4: Integrates Red Hat CoreOS as the default operating system for master and worker nodes, enhancing security and manageability.

Cluster Management and Updates

1. Operator Framework:
   • v3: Limited use of operators.
   • v4: Extensive use of operators for managing cluster components, making upgrades and maintenance more automated and reliable.
2. Updates:
   • v3: Manual updates and less streamlined.
   • v4: Offers automated, over-the-air updates for the cluster, including the operating system, Kubernetes, and cluster services.

Networking

1. SDN (Software Defined Networking):
   • v3: Uses OpenShift SDN with various plug-in options.
   • v4: Continues with OpenShift SDN but improves network capabilities and supports additional CNI (Container Network Interface) plug-ins.

Storage

1. Persistent Storage:
   • v3: Uses traditional storage solutions.
   • v4: Enhances storage options with better integration of cloud-native storage solutions.

Application Development and Deployment

1. Developer Tools:
   • v3: Traditional CI/CD methods.
   • v4: Improved developer tools and integration with CI/CD pipelines, including new tools like CodeReady Containers for simplified local development.
2. Container Orchestration:
   • Both versions are based on Kubernetes, but v4 includes more recent Kubernetes releases with new features and enhancements.

Cloud Integration

1. Cloud-Native Features:
   • v4: Stronger integration with cloud-native features and services, making it more adaptable to hybrid and multi-cloud environments.

Security

1. Security Enhancements:
   • v4: Enhanced security features, especially with the integration of Red Hat CoreOS and more robust RBAC (Role-Based Access Control).

Next: Brief explanation of OpenShift Nodes