VM Import Controller

Overview

Designed and implemented a Kubernetes operator to orchestrate large-scale virtual machine migrations from KVM to Harvester. This solution enabled the migration of 100+ VMs — a transition that was not operationally feasible without custom orchestration.

Key Achievements

• 🚀 100+ VMs migrated — Enabled enterprise-scale virtualization modernization
• ⚙️ Custom orchestration — Built where no off-the-shelf solution existed
• 🔄 Seamless transitions — Zero-downtime migration workflows

Technical Details

The operator implements a sophisticated reconciliation loop that:

1. Discovers source VMs via SSH connection to KVM/Libvirt hosts
2. Gracefully powers off source VMs with configurable timeouts
3. Streams and converts disk images using qemu-img
4. Creates KubeVirt VirtualMachine CRs with appropriate CPU/memory/network mappings
5. Tracks migration status via Kubernetes custom resource status fields

Architecture

┌─────────────────┐     ┌──────────────────┐     ┌─────────────────┐
│   KVM Source    │────▶│  VM Import       │────▶│   Harvester     │
│   (Libvirt)     │ SSH │  Controller      │     │   (KubeVirt)    │
└─────────────────┘     └──────────────────┘     └─────────────────┘

Technologies

Go Kubernetes Operator SDK KubeVirt Harvester Libvirt QEMU