KubeVirt

Overview

• VMs not going away—still a significant number of searches
• KubeVirt marries VMs and Kubernetes
• Operator plus CRDs
• Maps workloads to Pods
• Declarative—desired state of VM
• VMs run in Pods—same tools etc.
• Extends API—kubectl etc.
• virtctl—optional CLI tool
  • More convenience e.g. graphical desktops
• Start, stop, live migration
• Multi-network
• SR-IOV
• Block storage (PVs)
• Snapshots

Benefits

• Develop on and use one platform—developer self-service
• Kube-on-kube—Kubernetes running on KubeVirt VMs
  • Underlying cluster—infra cluster
• Operate one platform
• Kubernetes at heart
  • Extend to support legacy apps as long as required
• Long term goal—Kuebrnetes
• Scale one platform

Challenges

• Opinionated virt-operator deployment model
  • Customizations complex
• virt-operator requires many privileges
• Self-signed certs and CAs
  • Not always desirable—might have own CA
• No support for custom kubelet path
• Requirement for NET_RAW

Use Cases

• VM template generation
• Create Dev envs
• Kube-in-kube
• Nested virtualization
  • Run VMs within Kubernetes clusters running on VMs
• Appliances, other OSes
  • Unable to run in containers

Architecture

Tips

• Test suite in KubeVirt codebase
  • Run as Cron to continuously test that KubeVirt is working correctly
• Prometheus endpoints
• Deploy Containerized Data Importer (CDI)
  • Import data in PVs