DIY: Create Your Own Cloud with Kubernetes (Part 2)

To build a cloud using Kubernetes, virtualization is necessary due to the insufficient isolation provided by containers. KubeVirt is a popular virtualization technology for Kubernetes, allowing traditional virtual machines to be run using the Kubernetes API. Virtual machines are crucial for multi-tenancy isolation in cloud environments. KubeVirt utilizes the Container Storage Interface (CSI) for storage, which can handle both filesystems and block devices. Block devices are more efficient for virtual machines and enable live migration. External or internal storage solutions can be used, with LINSTOR being a ready-to-use option providing optimal performance and resource utilization. Kubernetes networking is complex, consisting of four layers, including the node network, pod network (CNI plugin), services network, and external traffic load balancer. Kube-OVN is a CNI plugin that provides a complete network solution for virtual machines in Kubernetes, supporting features like custom resources for IP and MAC address management, live migration, and virtual private cloud (VPC) creation. Cilium, based on eBPF technology, offers advanced networking capabilities, including services network functionality and enhanced security. Integrating Cilium and Kube-OVN provides a unified solution for seamless multi-tenant networking and advanced network policies. An external load balancer is required for accessing services from outside the cluster. By understanding these virtualization and networking technologies, you can effectively run virtual machines in Kubernetes and build a cloud infrastructure that meets your isolation, performance, and scalability requirements.