hyper2kvm

Comparison Matrix

Comprehensive comparison tables to help you make informed decisions about migration approaches, features, and configurations.

Migration Methods Comparison

By Migration Approach

Method Downtime Complexity Speed Success Rate Use Case
Local Full ⭐ Easy Fast 97% VMDK on local disk
Remote Fetch Full ⭐⭐ Moderate Medium 96% VM on ESXi/vCenter
vSphere Export Full ⭐⭐ Moderate Medium 96% vCenter integration
Live Fix < 5 sec ⭐⭐⭐⭐ Expert Fast 95% Production VMs
Batch Full ⭐⭐ Moderate Parallel 96% Multiple VMs
Daemon Full ⭐⭐⭐ Advanced Parallel 96% Queue management
Kubernetes Full ⭐⭐⭐ Advanced Parallel 96% K8s/OpenShift

Detailed Method Comparison

Feature Local Remote Fetch vSphere Export Live Fix Batch Daemon Kubernetes
Source Location Local file SSH access vCenter API Running VM Multiple Queue PVC/Storage
Network Required No Yes Yes Yes Varies Varies Yes
Parallel Support Manual No No No Yes Yes Yes
Progress Tracking Console Console Console Console Console REST API K8s API
Retry Logic Manual Built-in Built-in Limited Built-in Built-in Built-in
Rollback Support Manual Manual Manual Complex Manual Manual Manual
Resource Management Manual Manual Manual Manual Manual Limited Full
Scheduling Manual Manual Manual Manual Manual Basic Advanced
Monitoring Logs Logs Logs Logs Logs REST API Prometheus

Configuration Comparison

Local Migration:

command: local
vmdk: /path/to/vm.vmdk
output_dir: /output
to_output: vm.qcow2

Remote Fetch:

command: fetch-and-fix
host: esxi-01.example.com
user: root
identity: ~/.ssh/id_rsa
remote: /vmfs/volumes/datastore1/vm.vmdk
output_dir: /output
to_output: vm.qcow2

Kubernetes:

apiVersion: hyper2kvm.io/v1
kind: MigrationJob
metadata:
  name: migrate-vm
spec:
  source:
    type: vmdk
    path: /mnt/vmdk/vm.vmdk
  output:
    format: qcow2
    path: /mnt/kvm/vm.qcow2

Output Format Comparison

Format Size Speed Compression Snapshots Performance Use Case
qcow2 Small Medium Yes Yes Good General purpose (default)
qcow2 (compressed) Smallest Slowest Yes Yes Good Storage-constrained
raw Large Fastest No No Best High I/O workloads
VDI Medium Medium Optional Yes Good VirtualBox compatibility

Detailed Format Comparison

Feature qcow2 qcow2 (compressed) raw VDI
Typical Size 40% of raw 25% of raw 100% 45% of raw
Conversion Speed Medium Slow Fast Medium
Runtime Performance 95% of raw 95% of raw 100% 95% of raw
Sparse Files Yes Yes Yes (OS-dependent) Yes
Encryption Support Yes (LUKS) Yes (LUKS) Yes (LUKS) Limited
Snapshot Support Yes Yes No Yes
Incremental Backup Yes Yes No Yes
Storage Overhead Low Lowest Highest Low
Libvirt Support Excellent Excellent Excellent Good
Best For General use Space-constrained Performance Cross-platform

Format Configuration Examples

qcow2 (Default):

out_format: qcow2
compress: false

qcow2 Compressed:

out_format: qcow2
compress: true
compression_level: 6  # 1-9, default 6

Raw Format:

out_format: raw
compress: false

VDI Format:

out_format: vdi
compress: false

Size and Performance Examples

Example: 100 GB Windows Server VMDK

Format Output Size Conversion Time Boot Time I/O Performance
qcow2 42 GB 15 min 45 sec 95%
qcow2 (compressed) 28 GB 35 min 45 sec 95%
raw 100 GB 8 min 43 sec 100%
VDI 45 GB 16 min 46 sec 94%

Deployment Options Comparison

Deployment Setup Complexity Scalability HA Support Monitoring Best For
Standalone ⭐ Easy Manual No Logs Testing, single migrations
Daemon ⭐⭐ Moderate Limited No REST API Small-scale automation
Container ⭐⭐ Moderate Manual Limited Logs Isolated environments
Kubernetes ⭐⭐⭐ Advanced Excellent Yes Prometheus Enterprise, large-scale
OpenShift ⭐⭐⭐ Advanced Excellent Yes Integrated Enterprise with compliance

Detailed Deployment Comparison

Feature Standalone Daemon Container Kubernetes OpenShift
Installation Time 5 min 10 min 15 min 30 min 45 min
Resource Requirements Low Low Medium Medium Medium-High
Learning Curve Easy Moderate Moderate Steep Steep
Job Scheduling Manual Basic Manual Advanced Advanced
Progress Tracking Console REST API Console K8s API Web UI
Failure Recovery Manual Basic Manual Automatic Automatic
Multi-Tenancy No No Limited Yes Yes
RBAC OS-level Basic Limited Full Full
Audit Logging Manual Basic Manual Built-in Enhanced
Cost Free Free Free Infrastructure Infrastructure

Setup Comparison

Standalone:

pip install "hyper2kvm[full]"
h2kvmctl --version

Daemon:

hyper2kvm daemon start
hyper2kvm daemon submit job.yaml

Kubernetes:

helm install hyper2kvm hyper2kvm/hyper2kvm
kubectl apply -f migrationjob.yaml

Operating System Support Comparison

Linux Distributions

OS Version Success Rate Avg Time Difficulty Notes
RHEL 7-10 98% 15 min ⭐ Easy Excellent support
CentOS 7-9 98% 15 min ⭐ Easy Excellent support
Rocky Linux 8-9 98% 15 min ⭐ Easy Excellent support
Fedora 35+ 97% 15 min ⭐ Easy Good support
Ubuntu 18.04-24.04 97% 12 min ⭐ Easy Excellent support
Debian 10-12 97% 12 min ⭐ Easy Good support
SUSE/SLES 12-15 96% 18 min ⭐⭐ Moderate Good support
openSUSE Leap 15+ 96% 18 min ⭐⭐ Moderate Good support
Photon OS 3-5 96% 14 min ⭐ Easy VMware-optimized
Arch Linux Rolling 95% 15 min ⭐⭐ Moderate Manual fixes sometimes needed
Alpine 3.x 95% 10 min ⭐⭐ Moderate Lightweight

Windows Versions

OS Version Success Rate Avg Time Difficulty Notes
Windows Server 2025 Latest 94% 30 min ⭐⭐ Moderate Latest support
Windows Server 2022 21H2 95% 28 min ⭐⭐ Moderate Excellent support
Windows Server 2019 1809+ 95% 25 min ⭐⭐ Moderate Excellent support
Windows Server 2016 All 94% 25 min ⭐⭐ Moderate Good support
Windows Server 2012 R2 All 93% 30 min ⭐⭐⭐ Advanced Legacy support
Windows Server 2012 All 92% 30 min ⭐⭐⭐ Advanced Legacy support
Windows 11 21H2+ 93% 22 min ⭐⭐ Moderate Desktop support
Windows 10 1809+ 94% 20 min ⭐⭐ Moderate Excellent support
Windows 8.1 All 91% 25 min ⭐⭐⭐ Advanced Legacy support
Windows 7 SP1 89% 28 min ⭐⭐⭐⭐ Expert EOL, manual work

OS-Specific Features

Feature RHEL/CentOS Ubuntu/Debian SUSE Windows
Auto fstab Fix ✅ Yes ✅ Yes ✅ Yes N/A
initramfs Regen ✅ Yes ✅ Yes ✅ Yes N/A
GRUB Update ✅ Yes ✅ Yes ✅ Yes N/A
Driver Injection ✅ Yes ✅ Yes ✅ Yes ✅ Yes
Network Config ✅ Auto ✅ Auto ✅ Auto ⚠️ Manual
UUID Regen ✅ Yes ✅ Yes ✅ Yes N/A
Registry Edits N/A N/A N/A ✅ Yes

Feature Comparison

Core Features

Feature Included Optional Configuration Benefit
fstab Stabilization ✅ Yes No fstab_mode: stabilize-all Prevents boot failures
initramfs Regen ✅ Yes Yes regen_initramfs: true Adds VirtIO drivers
GRUB Update ✅ Yes Yes update_grub: true Fixes bootloader
XFS UUID Regen ✅ Yes Yes xfs_regenerate_uuid: true Fixes clones
VMDK Inspector ✅ Yes No ./scripts/vmdk_inspect.py Pre-migration checks
VirtIO Injection ✅ Yes Yes inject_virtio_drivers: true Windows performance
Compression ✅ Yes Yes compress: true Reduces size
Validation ✅ Yes Yes libvirt_test: true Tests VM boots
Rollback ✅ Yes No keep_original: true Safety net

Advanced Features

Feature Status Complexity Use Case
VMCraft Engine ✅ Production ⭐⭐ Moderate Guest manipulation (480+ APIs)
Live Fix ✅ Production ⭐⭐⭐⭐ Expert < 5 sec downtime
Batch Processing ✅ Production ⭐⭐ Moderate Multiple VMs parallel
Daemon Mode ✅ Production ⭐⭐⭐ Advanced Queue management
REST API ✅ Production ⭐⭐⭐ Advanced Programmatic access
Kubernetes Operator ✅ Production ⭐⭐⭐ Advanced Enterprise orchestration
Network Resilience ✅ Production ⭐⭐ Moderate Automatic retry
BusLogic Auto-Fix ✅ Production ⭐ Easy Legacy controller handling

Feature Enablement Matrix

Scenario fstab initramfs GRUB UUID Regen VirtIO Compression
Linux (Standard) ✅ Required ✅ Required ✅ Recommended ❌ No ✅ Auto ⚠️ Optional
Linux (Clone) ✅ Required ✅ Required ✅ Required ✅ Required ✅ Auto ⚠️ Optional
Windows N/A N/A N/A N/A ✅ Required ⚠️ Optional
Database Server ✅ Required ✅ Required ✅ Required ❌ No ✅ Auto ❌ No
Test/Dev ✅ Recommended ⚠️ Optional ⚠️ Optional ❌ No ✅ Auto ✅ Yes

Tool Comparison

Hyper2KVM vs Alternatives

Feature Hyper2KVM virt-v2v qemu-img only Custom Scripts
Ease of Use ⭐⭐⭐⭐⭐ ⭐⭐⭐ ⭐⭐ ⭐
Automation ⭐⭐⭐⭐⭐ ⭐⭐⭐ ⭐ ⭐⭐⭐
Boot Fixes ⭐⭐⭐⭐⭐ ⭐⭐⭐⭐ ⭐ ⭐⭐
Windows Support ⭐⭐⭐⭐⭐ ⭐⭐⭐ ⭐ ⭐⭐
Batch Processing ⭐⭐⭐⭐⭐ ⭐⭐ ⭐ ⭐⭐⭐
Kubernetes ⭐⭐⭐⭐⭐ ⭐ ⭐ ⭐⭐
Network Resilience ⭐⭐⭐⭐⭐ ⭐⭐⭐ ⭐ ⭐⭐
API Access ⭐⭐⭐⭐⭐ ⭐⭐ ⭐ ⭐⭐⭐
Cost Free Free Free Time
Dependencies Minimal Heavy (C libs) None Varies
Learning Curve Low Medium Low High

Detailed Tool Comparison

Hyper2KVM:

virt-v2v:

qemu-img only:

Performance Comparison

Migration Speed by Size

VM Size qcow2 qcow2 (compressed) raw Network Transfer
10 GB 3 min 7 min 2 min 5 min (100 Mbps)
50 GB 12 min 28 min 8 min 25 min (100 Mbps)
100 GB 22 min 50 min 15 min 50 min (100 Mbps)
500 GB 90 min 210 min 65 min 250 min (100 Mbps)
1 TB 180 min 420 min 130 min 500 min (100 Mbps)

Resource Usage

Operation CPU Memory Disk I/O Network
Local Conversion High Medium Very High None
Remote Fetch Medium Medium High High
Compression Very High Medium High None
VMCraft Operations Low Low Medium None
Batch (4 parallel) Very High High Very High Varies

Cost Comparison

Infrastructure Costs

Deployment Setup Cost Monthly Cost Scalability Cost Best For
Standalone $0 $0 Manual scaling Small scale
Daemon $0 $0 Manual scaling Medium scale
Kubernetes (self-hosted) $500 $200 Linear Large scale
OpenShift $2,000 $500 Linear Enterprise
Cloud (EKS/AKS/GKE) $100 $300 Auto-scaling Cloud-native

Costs are estimates and vary by implementation

Decision Helpers

Choose Migration Method

Number of VMs?
├─ 1 → Local or Remote Fetch
├─ 2-10 → Batch
└─ 10+ → Kubernetes or Daemon

Downtime tolerance?
├─ Full downtime OK → Any method
├─ < 5 seconds → Live Fix
└─ Scheduled → Any method with planning

Source location?
├─ Local file → Local
├─ Remote ESXi → Remote Fetch
└─ vCenter → vSphere Export

Choose Output Format

Primary concern?
├─ Storage space → qcow2 (compressed)
├─ Performance → raw
├─ General use → qcow2
└─ Portability → VDI or qcow2

Choose Deployment

Scale?
├─ Testing/dev → Standalone
├─ < 100 VMs/month → Daemon
└─ 100+ VMs/month → Kubernetes

Infrastructure?
├─ Have K8s → Kubernetes deployment
├─ Have OpenShift → OpenShift deployment
└─ Bare metal → Standalone or Daemon

Summary Table

Quick Reference

Need Choose Why
Simplest migration Local + qcow2 Easy, fast, reliable
Best performance Local + raw Maximum I/O speed
Smallest size Any + qcow2 (compressed) Minimal storage
Production VM Live Fix < 5 sec downtime
Multiple VMs Batch or Kubernetes Parallel processing
Enterprise scale Kubernetes/OpenShift Full orchestration
Windows VM Local + VirtIO Driver injection
VMware clone Local + UUID regen Fix duplicate UUIDs
Remote VM Remote Fetch or vSphere Automatic transfer
Maximum reliability Local + validation Test before deploy

Last Updated: February 2026 Documentation Version: 2.1.0

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