Comprehensive glossary of terms, concepts, and technologies used in Hyper2KVM.
- Core Concepts
- Migration Terms
- VMCraft Terms
- Virtualization Technologies
- File Systems & Storage
- Networking
- Kubernetes & Orchestration
- Operating Systems
- Tools & Utilities
- Acronyms
A JSON document that describes migration outputs (disk images, configuration files, metadata). Follows the artifact-manifest-v1.0 schema specification.
Change root - a Unix operation that changes the apparent root directory. Hyper2KVM uses enhanced chroot with proper isolation and cleanup.
Migration performed while the VM is powered off. Allows complete filesystem access and modification.
The process of transforming a VM disk image from one format to another (e.g., VMDK to QCOW2).
Hyper2KVM's improved chroot implementation with automatic mount/unmount of /proc, /sys, /dev and safe cleanup.
File System Table - Linux configuration file (/etc/fstab) that defines how disk partitions, block devices, or remote filesystems should be mounted.
The virtual machine being migrated or manipulated. The operating system and applications running inside the VM.
The physical or virtual machine running the hypervisor and hosting guest VMs.
Migration of a running VM with minimal downtime. Hyper2KVM's "live fix" mode uses SSH to apply fixes while the VM is running.
The complete process of converting a VM from one platform (VMware/Hyper-V) to another (KVM).
Post-migration remediation performed on a stopped VM to fix boot issues or configuration problems.
The original virtualization platform (VMware ESXi, vSphere, Hyper-V) from which VMs are being migrated.
The destination virtualization platform (KVM, QEMU, OpenStack, oVirt) to which VMs are being migrated.
Hyper2KVM's native Python VM manipulation engine with 480+ APIs for guest filesystem operations.
Migrating multiple VMs in parallel or sequence using daemon mode or automation scripts.
Automatic detection and remediation of legacy BusLogic SCSI controllers that don't boot properly on KVM.
The time required to convert a VMDK to QCOW2, typically 5-60 minutes depending on size and compression.
Converting fstab entries from device names (/dev/sda1) to stable identifiers (UUID or LABEL).
Modular components in Hyper2KVM that apply specific fixes (e.g., initramfs regeneration, GRUB updates).
Initial RAM filesystem - a temporary root filesystem loaded during Linux boot before the real root filesystem is mounted.
YAML configuration file defining migration parameters (source VMDK, output path, options).
The sequence of operations performed during migration: fetch → convert → fix → validate → export.
Checks performed before migration to identify potential issues (VMDK Inspector, compatibility checks).
Reverting migration changes if issues are detected. Hyper2KVM maintains original files for safety.
Making configurations more robust for the target platform (fstab stabilization, UUID regeneration).
Percentage of migrations that complete successfully and boot on the target platform. Hyper2KVM achieves 96.5% for Linux, 94% for Windows.
Fixing duplicate XFS filesystem UUIDs that occur when VMware VMs are cloned.
VMCraft provides 480+ APIs for guest manipulation, covering filesystem, packages, services, and configuration.
Configuration file editing library integrated into VMCraft for safe manipulation of system configuration files.
Analyzing a VM disk to detect OS type, installed packages, services, and configuration.
Command-line tool from libguestfs for manual VM manipulation. VMCraft provides similar capabilities natively.
C library for accessing and modifying VM disk images. VMCraft is a pure-Python alternative.
Logical Volume Manager support in VMCraft for accessing LVM-based filesystems within VMs.
Protocol for accessing block devices over a network. Used by VMCraft to mount QCOW2 images.
Automatic identification of the guest operating system (distribution, version, architecture).
VMCraft's ability to query and manipulate packages using yum, dnf, apt, zypper within guest filesystems.
VMCraft's capability to read and modify Windows Registry hives for driver injection and configuration.
VMCraft APIs for enabling/disabling systemd services or SysV init scripts within guests.
Paravirtualized drivers for optimal performance on KVM. VMCraft can inject these into Windows VMs.
VMware's bare-metal hypervisor platform. Common source platform for migrations.
Microsoft's hypervisor technology. Hyper2KVM can migrate from Hyper-V to KVM.
Tools for managing hypervisor-native virtualization. Hyper2KVM integrates with these for advanced deployments.
Linux kernel module that turns Linux into a hypervisor. The target platform for Hyper2KVM migrations.
Kubernetes extension for running VMs alongside containers. Hyper2KVM can deploy to KubeVirt clusters.
Virtualization management library. Hyper2KVM can integrate with libvirt for VM management.
Cloud computing platform. Hyper2KVM can export VMs in OpenStack-compatible formats.
Open-source virtualization management platform based on KVM.
Quick Emulator - the userspace component of KVM that performs hardware emulation.
Agent running inside VMs for advanced management operations and better integration.
VMware's centralized management platform for vSphere environments.
Red Hat's V2V (Virtual-to-Virtual) conversion tool. Hyper2KVM is an alternative with additional features.
VMware's disk image format. The typical source format for migrations.
VMware's virtualization platform suite including ESXi and vCenter.
B-tree filesystem - a modern Linux filesystem with advanced features.
A copy of a VM created using VMware's clone feature. Often has duplicate UUIDs requiring regeneration.
Linux kernel framework for mapping block devices. Used for LVM, encryption, and other storage features.
A file containing the complete contents of a disk (VMDK, QCOW2, RAW, VHD).
Fourth Extended Filesystem - the most common Linux filesystem.
Universally Unique Identifier assigned to a filesystem. Critical for proper mounting.
stabilize-all: Convert all entries to UUIDuuid-only: Only update UUID entrieslabel-fallback: Prefer UUID, fallback to LABELpreserve: Keep original entries
System for managing logical volumes that can span multiple physical disks.
New Technology File System - Microsoft's filesystem for Windows.
Data structure describing the partitions on a disk (MBR or GPT).
QEMU Copy-On-Write version 2 - KVM's native disk image format with compression and snapshots.
Uncompressed disk image format. Larger but slightly faster than QCOW2.
A file with holes (unallocated regions) that takes less disk space. QCOW2 images are sparse by default.
128-bit identifier used for filesystems, partitions, and other resources.
Virtual Hard Disk - Microsoft's disk image format used by Hyper-V.
High-performance 64-bit journaling filesystem. Commonly used in enterprise Linux.
Virtual network switch that connects VMs to physical networks.
Protocol for automatic IP address assignment. Often configured in migrated VMs.
Media Access Control address - unique identifier for network interfaces.
Network configuration where VMs share the host's IP address.
Hyper2KVM's ability to handle network failures during remote operations (retry, exponential backoff).
Manually configured IP address (as opposed to DHCP). Requires configuration preservation during migration.
Network segmentation technology. May need reconfiguration after migration.
Kubernetes object for storing configuration data. Used to provide migration manifests.
Kubernetes extension mechanism. Hyper2KVM defines MigrationJob, OfflineFixJob, and InspectionJob CRDs.
Kubernetes package manager. One deployment method for Hyper2KVM.
Kubernetes resource for running batch tasks. Hyper2KVM migrations run as Kubernetes Jobs.
Kubernetes logical cluster division. Hyper2KVM typically runs in dedicated namespaces.
Framework for managing Kubernetes operators. Alternative deployment method for Hyper2KVM.
Red Hat's Kubernetes distribution with additional enterprise features.
Kubernetes extension for managing complex applications. Hyper2KVM provides operators for automation.
Kubernetes resource for requesting persistent storage for migration artifacts.
Kubernetes node that runs workload pods. Hyper2KVM workers run on worker nodes.
Hyper2KVM's REST API for job submission and management in Kubernetes environments.
Community Enterprise Operating System - free derivative of RHEL. Well-supported by Hyper2KVM.
VMware's minimal Linux distribution optimized for cloud-native applications.
Commercial Linux distribution. Fully supported including RHEL 10.
Community enterprise Linux distribution, RHEL-compatible successor to CentOS.
SUSE Linux Enterprise Server - enterprise Linux distribution with full support.
Popular Debian-based Linux distribution. Supported including Ubuntu 24.04.
Microsoft Windows operating systems. Hyper2KVM supports Windows Server and Desktop editions with VirtIO driver injection.
Hyper2KVM's command-line interface tool for migrations and management.
Linux bootloader. Hyper2KVM can regenerate GRUB configuration for the new platform.
Formal specification for JSON document structure. Used for artifact manifest validation.
Linux utility for listing block devices. Used in migration diagnostics.
QEMU disk image utility for conversion, compression, and manipulation.
Modern Linux init system and service manager. Hyper2KVM integrates as a systemd service.
Hyper2KVM's interactive terminal interface for user-friendly migrations.
Hyper2KVM tool for analyzing VMDK files before migration to detect potential issues.
YAML Ain't Markup Language - human-readable data serialization format used for migration manifests.
| Acronym | Full Name | Description |
|---|---|---|
| API | Application Programming Interface | Programmatic interface for software interaction |
| BIOS | Basic Input/Output System | Firmware interface for PC initialization |
| CLI | Command-Line Interface | Text-based user interface |
| CPU | Central Processing Unit | Main processor in a computer |
| CRD | Custom Resource Definition | Kubernetes API extension |
| DHCP | Dynamic Host Configuration Protocol | Network configuration protocol |
| DNS | Domain Name System | Hostname to IP address resolution |
| ESXi | Elastic Sky X integrated | VMware's bare-metal hypervisor |
| GRUB | GRand Unified Bootloader | Linux boot loader |
| GUI | Graphical User Interface | Visual user interface |
| HTTP | Hypertext Transfer Protocol | Web communication protocol |
| IDE | Integrated Drive Electronics | Legacy disk interface (also: Integrated Development Environment) |
| I/O | Input/Output | Data transfer operations |
| IP | Internet Protocol | Network addressing protocol |
| JSON | JavaScript Object Notation | Data interchange format |
| KVM | Kernel-based Virtual Machine | Linux virtualization technology |
| LVM | Logical Volume Manager | Linux storage management |
| MAC | Media Access Control | Network hardware address |
| MBR | Master Boot Record | Legacy partition table format |
| NAT | Network Address Translation | IP address translation |
| NBD | Network Block Device | Block device over network protocol |
| NFS | Network File System | Distributed file system protocol |
| NTFS | New Technology File System | Windows filesystem |
| OLM | Operator Lifecycle Manager | Kubernetes operator management |
| OS | Operating System | System software managing hardware |
| PVC | PersistentVolumeClaim | Kubernetes storage request |
| QCOW2 | QEMU Copy-On-Write v2 | KVM disk image format |
| QEMU | Quick Emulator | Hardware emulation software |
| RAM | Random Access Memory | Computer memory |
| REST | Representational State Transfer | Web API architectural style |
| RHEL | Red Hat Enterprise Linux | Commercial Linux distribution |
| RPM | RPM Package Manager | Package management system |
| SAN | Storage Area Network | Dedicated storage network |
| SCSI | Small Computer System Interface | Storage device interface |
| SLES | SUSE Linux Enterprise Server | Enterprise Linux distribution |
| SSH | Secure Shell | Encrypted remote access protocol |
| SSL/TLS | Secure Sockets Layer / Transport Layer Security | Encryption protocols |
| SysV | System V | Traditional Unix init system |
| TCP | Transmission Control Protocol | Network transport protocol |
| TUI | Text User Interface | Terminal-based interface |
| UEFI | Unified Extensible Firmware Interface | Modern firmware interface |
| URL | Uniform Resource Locator | Web address |
| USB | Universal Serial Bus | Peripheral device interface |
| UUID | Universally Unique Identifier | 128-bit unique identifier |
| V2V | Virtual-to-Virtual | VM migration between platforms |
| VHD | Virtual Hard Disk | Hyper-V disk image format |
| VLAN | Virtual Local Area Network | Network segmentation |
| VM | Virtual Machine | Emulated computer system |
| VMDK | Virtual Machine Disk | VMware disk image format |
| VNC | Virtual Network Computing | Remote desktop protocol |
| YAML | YAML Ain't Markup Language | Data serialization format |
Use your browser's search function (Ctrl+F / Cmd+F) to quickly locate terms in this glossary.
For more detailed information about specific topics:
- Migration concepts: See Tutorials
- VMCraft APIs: See Features Documentation
- Technical details: See Reference Documentation
- Troubleshooting: See FAQ
Found a missing term? Want to improve a definition?
- Check if the term is already defined
- Ensure the definition is clear and accurate
- Add relevant cross-references
- Submit a pull request
See: Contributing Guide
Last Updated: February 2026 Hyper2KVM Version: 2.1.0 Total Terms: 150+ Categories: 10
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