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libvirt-playbooks

Ansible playbooks to automate virtual machine creation and management on Fedora 42+ using libvirt and KVM.

Features

  • Automated libvirt setup - Installs and configures all required packages
  • VM creation - Easily create VMs with customizable specs
  • VM configuration - Post-creation setup with SSH, packages, and hostname
  • Multiple network interfaces - Configure VMs with multiple NICs, custom MAC addresses, and different virtual networks
  • Multiple disk volumes - Attach multiple disks to VMs with custom sizes, formats, and device names
  • ISO mounting - Mount ISO images as CDROM for OS installation
  • ISO management - Download and manage ISO images from URLs
  • Storage management - Automatic storage pool creation and management
  • Role-based structure - Modular, reusable Ansible roles
  • Remote host support - Manage VMs on remote Fedora 42+ hosts via SSH
  • Unified VM management - Single playbook handles both single and multiple VM creation

Requirements

  • Host: Fedora 42 or higher
  • CPU: Virtualization extensions enabled (Intel VT-x or AMD-V)
  • RAM: Minimum 4GB (8GB+ recommended for multiple VMs)
  • Storage: At least 20GB free space for VMs
  • Ansible: 2.12+
  • Python: 3.9+

Installation

  1. Clone the repository:
git clone https://github.com/jeffdyoung/libvirt-playbooks.git
cd libvirt-playbooks
  1. Install Ansible and dependencies:
sudo dnf install -y ansible python3-libvirt python3-lxml
  1. Install required Ansible collections:
ansible-galaxy collection install community.libvirt
ansible-galaxy collection install ansible.posix
  1. Create your host-specific configuration:
# Copy example files as templates
cp host_vars/aarch64-002.sys.eng.rdu2.dc.redhat.com.yml.example \
   host_vars/your-hostname.yml

# Edit with your VM definitions
vim host_vars/your-hostname.yml

Note: Host-specific files (host_vars/*.yml and inventory.yml) are excluded from version control via .gitignore to prevent committing sensitive host data. Only example files are tracked.

Project Structure

libvirt-playbooks/
├── ansible.cfg                    # Ansible configuration
├── inventory                      # Host inventory (INI format)
├── inventory.yml.example          # Extended YAML inventory example with VM definitions
├── setup_libvirt.yml             # Main libvirt setup playbook
├── manage_host_vms.yml           # Unified VM creation and configuration playbook
├── manage_host_storage.yml       # Storage pool and directory management playbook
├── manage_host_network.yml       # Virtual network management playbook
├── reset_host.yml                # Reset host by removing all VMs, networks, and storage
├── complete_workflow.yml         # Combined setup + VM creation
├── setup_remote_host.sh          # Remote host preparation script
├── README.md                     # This file
├── templates/                    # Network XML templates
│   ├── network_nat.xml.j2        # NAT network template
│   ├── network_isolated.xml.j2   # Isolated network template
│   └── network_bridge.xml.j2     # Bridge network template
├── roles/
│   ├── libvirt-setup/            # Role to setup libvirt on host
│   │   ├── tasks/
│   │   ├── templates/
│   │   └── handlers/
│   ├── vm-create/                # Role to create VMs
│   │   ├── tasks/
│   │   └── templates/
│   └── vm-configure/             # Role to configure VMs
│       └── tasks/
├── group_vars/
│   └── libvirt_hosts.yml         # Default variables for all hosts
├── host_vars/                    # Host-specific variables and VM definitions
│   ├── *.yml                     # Actual host configurations (gitignored)
│   ├── *.yml.example             # Example host variable files
│   └── README.md                 # Documentation for host_vars
└── group_files/
    └── vm_examples.yml           # Example VM definitions

Quick Start

Note: This project uses Ansible playbooks exclusively. All operations are performed via ansible-playbook commands.

Quick Reference

Task Command
Setup libvirt on hosts ansible-playbook -i inventory setup_libvirt.yml
Setup storage pools ansible-playbook -i inventory manage_host_storage.yml
Download ISOs ansible-playbook -i inventory manage_host_storage.yml --tags iso
Create virtual networks ansible-playbook -i inventory manage_host_network.yml
Create single VM ansible-playbook -i inventory manage_host_vms.yml -e "vm_name=myvm"
Create VMs from inventory ansible-playbook -i inventory manage_host_vms.yml
Create VMs (skip config) ansible-playbook -i inventory manage_host_vms.yml --skip-tags configure
Reset host (remove all VMs) ansible-playbook -i inventory reset_host.yml -l hostname
List all VMs virsh list --all
List all networks virsh net-list --all
Start VM virsh start <vm_name>
Stop VM virsh shutdown <vm_name>

1. Configure Inventory

Edit the inventory file to specify your target host(s):

Local operations (via SSH to 127.0.0.1):

[libvirt_hosts]
127.0.0.1 ansible_user=root ansible_port=22

Remote hosts:

[libvirt_hosts]
aarch64.host.com ansible_user=<youruser> ansible_port=22
x86.host.com ansible_user=<youruser> ansible_port=22

See inventory.yml.example for YAML format with VM definitions.

2. Setup libvirt on your host

ansible-playbook -i inventory setup_libvirt.yml

This will:

  • Update system packages
  • Install libvirt, QEMU, and related tools
  • Enable and start the libvirt service
  • Create storage directories
  • Configure storage pools
  • Set up proper permissions

3. Create VMs

ansible-playbook -i inventory manage_host_vms.yml

Usage Examples

Example 1: Simple setup and VM creation

# Step 1: Setup libvirt (run once)
ansible-playbook -i inventory setup_libvirt.yml

# Step 2: Create and configure a development VM
ansible-playbook -i inventory manage_host_vms.yml \
  -e "vm_name=dev-box" \
  -e "vm_memory_mb=4096" \
  -e "vm_vcpus=4" \
  -e "vm_disk_size_gb=50"

# Or skip configuration step
ansible-playbook -i inventory manage_host_vms.yml \
  -e "vm_name=dev-box" \
  --skip-tags configure

Example 2: Create multiple VMs

Create a file extra_vars.yml:

vm_definitions:
  - name: web-server
    memory: 2048
    vcpus: 2
    disk_size: 30
  - name: db-server
    memory: 4096
    vcpus: 4
    disk_size: 50
  - name: app-server
    memory: 3072
    vcpus: 3
    disk_size: 40

Then run:

ansible-playbook -i inventory complete_workflow.yml -e "@extra_vars.yml"

Example 3: Create single VM without configuration

Sometimes you only want to create VMs quickly without waiting for configuration:

# Create VM without configuring it
ansible-playbook -i inventory manage_host_vms.yml \
  -e "vm_name=test-vm" \
  --skip-tags configure

# Or create multiple VMs from inventory without configuring them
ansible-playbook -i inventory.yml manage_host_vms.yml \
  --skip-tags configure

Example 4: Multi-host operations

Target specific hosts from inventory:

# Run on local host only
ansible-playbook -i inventory setup_libvirt.yml -l 127.0.0.1

# Run on specific remote host
ansible-playbook -i inventory setup_libvirt.yml -l aarch64-002.sys.eng.rdu2.dc.redhat.com

# Run on all hosts
ansible-playbook -i inventory setup_libvirt.yml

Example 5: Define VMs in inventory (YAML format)

Create or edit inventory.yml with VM definitions per host:

libvirt_hosts:
  hosts:
    aarch64-dev:
      ansible_host: aarch64-002.sys.eng.rdu2.dc.redhat.com
      ansible_user: root
      ansible_port: 22
      # Define VMs for this host
      vms:
        - name: dev-vm-001
          memory: 4096
          vcpus: 4
          disk_size: 50
          autostart: true
          networks:
            - name: default
              mac: "52:54:00:11:22:01"
            - name: storage-network
              mac: "52:54:00:aa:bb:01"
        - name: dev-vm-002
          memory: 4096
          vcpus: 4
          disk_size: 50
          autostart: true
          networks:
            - name: default
              mac: "52:54:00:11:22:02"
        - name: test-vm-001
          memory: 2048
          vcpus: 2
          disk_size: 30
          autostart: false
          # networks parameter is optional - defaults to single NIC on 'default' network

Then create and configure all VMs:

# Create and configure all VMs defined in inventory for all hosts
ansible-playbook -i inventory.yml manage_host_vms.yml

# Create and configure VMs for specific host only
ansible-playbook -i inventory.yml manage_host_vms.yml -l aarch64-dev

# Create VMs without configuration (faster)
ansible-playbook -i inventory.yml manage_host_vms.yml --skip-tags configure

Example 6: Define VMs using host_vars

Create host_vars/aarch64-002.sys.eng.rdu2.dc.redhat.com.yml:

vms:
  - name: ocp-master-1
    memory: 16384
    vcpus: 8
    disk_size: 120
    autostart: true
    networks:
      - name: default
        mac: "52:54:00:11:22:01"
      - name: storage-network
        mac: "52:54:00:aa:bb:01"
  - name: ocp-worker-1
    memory: 32768
    vcpus: 16
    disk_size: 200
    autostart: true
    networks:
      - name: default
        mac: "52:54:00:11:22:02"
      - name: storage-network
        mac: "52:54:00:aa:bb:02"

Then create and configure the VMs:

# Create and configure all VMs
ansible-playbook -i inventory manage_host_vms.yml -l aarch64-002.sys.eng.rdu2.dc.redhat.com

# Only create VMs (skip configuration)
ansible-playbook -i inventory manage_host_vms.yml -l aarch64-002.sys.eng.rdu2.dc.redhat.com --skip-tags configure

# Only configure already-created VMs
ansible-playbook -i inventory manage_host_vms.yml -l aarch64-002.sys.eng.rdu2.dc.redhat.com --tags configure

Example 7: Multi-NIC VMs for OpenShift cluster

For complex setups like OpenShift clusters with separate networks for management, storage, and application traffic:

Create host_vars/aarch64-002.sys.eng.rdu2.dc.redhat.com.yml:

vms:
  - name: ocp-master-1
    memory: 16384
    vcpus: 8
    disk_size: 120
    autostart: true
    networks:
      - name: default              # Management network
        mac: "52:54:00:10:00:01"
      - name: storage-network       # Storage/Ceph network
        mac: "52:54:00:20:00:01"
      - name: app-network          # Application traffic network
        mac: "52:54:00:30:00:01"

  - name: ocp-worker-1
    memory: 32768
    vcpus: 16
    disk_size: 200
    autostart: true
    networks:
      - name: default
        mac: "52:54:00:10:00:02"
      - name: storage-network
        mac: "52:54:00:20:00:02"
      - name: app-network
        mac: "52:54:00:30:00:02"

  - name: ocp-worker-2
    memory: 32768
    vcpus: 16
    disk_size: 200
    autostart: true
    networks:
      - name: default
        mac: "52:54:00:10:00:03"
      - name: storage-network
        mac: "52:54:00:20:00:03"
      - name: app-network
        mac: "52:54:00:30:00:03"

Then create the cluster:

# Create all VMs with their network configurations
ansible-playbook -i inventory manage_host_vms.yml -l aarch64-002.sys.eng.rdu2.dc.redhat.com

Note: Ensure the custom networks (storage-network, app-network) are created in libvirt before running the playbook. See the Network Configuration section for details on creating virtual networks.

VM Configuration

VM configuration happens automatically after creation when using manage_host_vms.yml. The configuration step will:

  • Wait for SSH connectivity
  • Set hostname
  • Update system packages
  • Install common tools
  • Configure SSH key-based authentication

You can control configuration with tags:

# Create and configure (default behavior)
ansible-playbook -i inventory manage_host_vms.yml -e "vm_name=myvm"

# Only create, skip configuration
ansible-playbook -i inventory manage_host_vms.yml -e "vm_name=myvm" --skip-tags configure

# Only configure existing VMs (without creating)
ansible-playbook -i inventory manage_host_vms.yml --tags configure

Defining VMs

There are multiple ways to define VMs in this project:

Method 1: Command-line (single VM)

Create a single VM using command-line parameters:

ansible-playbook -i inventory manage_host_vms.yml \
  -e "vm_name=myvm" \
  -e "vm_memory_mb=4096" \
  -e "vm_vcpus=4"

Method 2: Inventory YAML (multiple VMs per host)

Define VMs directly in a YAML inventory file:

libvirt_hosts:
  hosts:
    aarch64-dev:
      ansible_host: aarch64-002.sys.eng.rdu2.dc.redhat.com
      ansible_user: root
      vms:
        - name: vm1
          memory: 4096
          vcpus: 4
          disk_size: 50
          networks:
            - name: default
              mac: "52:54:00:11:22:01"
        - name: vm2
          memory: 2048
          vcpus: 2
          disk_size: 30
          networks:
            - name: default

Use: ansible-playbook -i inventory.yml manage_host_vms.yml

Method 3: host_vars directory (multiple VMs per host)

Create host_vars/<hostname>.yml:

vms:
  - name: vm1
    memory: 4096
    vcpus: 4
    disk_size: 50
    networks:
      - name: default
        mac: "52:54:00:11:22:01"
      - name: storage-network
        mac: "52:54:00:aa:bb:01"
  - name: vm2
    memory: 2048
    vcpus: 2
    disk_size: 30
    networks:
      - name: default

Use: ansible-playbook -i inventory manage_host_vms.yml -l <hostname>

Method 4: Extra vars file (cluster setup)

Create a vars file with VM definitions:

# cluster.yml
vm_definitions:
  - name: master
    memory: 4096
    vcpus: 4
  - name: worker1
    memory: 2048
    vcpus: 2

Use: ansible-playbook -i inventory complete_workflow.yml -e "@cluster.yml"

Available Variables

Global variables (group_vars/libvirt_hosts.yml)

Variable Default Description
libvirt_enabled true Enable libvirt
libvirt_storage_path /home/{{ ansible_user }}/libvirt Default storage path for all libvirt data
libvirt_network_name default Network name
vm_memory_mb 2048 Default VM memory in MB
vm_vcpus 2 Default number of vCPUs
vm_disk_size_gb 20 Default disk size in GB
vm_os_variant fedora42 OS variant for virt-install
vm_network_bridge virbr0 Network bridge
vm_dns_servers 8.8.8.8, 8.8.4.4 DNS servers

Storage Configuration:

  • By default, all libvirt data (VM images, ISOs, cloud images) is stored in a single directory: libvirt_storage_path
  • Override the default path in host_vars: libvirt_storage_path: /mnt/nvme/libvirt
  • Create additional custom storage pools using the storage_pools variable (see Storage Pools section)

VM-specific variables

Variable Required Description
vm_name Yes Name of the VM
vm_memory_mb No Memory in MB
vm_vcpus No Number of vCPUs
vm_disk_size_gb No Disk size in GB (primary OS disk)
vm_autostart No Enable autostart (true/false)
vm_hostname No Hostname inside the VM
vm_user No Default user (default: root)
vm_networks No List of network configurations (see Network Configuration section)
vm_volumes No List of additional disk volumes (see Volume Configuration section)
vm_iso No ISO filename or full path to mount as CDROM (see ISO Mount section)
vm_mac No (Deprecated) Use vm_networks instead for network configuration

Storage Pools Configuration

By default, all libvirt data is stored in a single directory (libvirt_storage_path). You can create additional custom storage pools for different purposes or storage devices.

Default storage

The default storage pool is automatically created at:

libvirt_storage_path: /home/<user>/libvirt

All VM images, ISOs, and cloud images are stored here by default.

Overriding default storage location

Change the default location in host_vars:

libvirt_storage_path: /mnt/nvme/libvirt

Creating custom storage pools

Define additional storage pools for high-performance storage, archives, or different mount points:

storage_pools:
  - name: nvme-fast
    path: /mnt/nvme/libvirt
  - name: ssd-pool
    path: /mnt/ssd/libvirt
  - name: archive-pool
    path: /mnt/archive/libvirt

Storage pool parameters

Parameter Required Description
name Yes Unique pool name
path Yes Full path to storage directory

Using custom pools with VMs

Specify the full path when defining VM volumes:

vms:
  - name: high-performance-vm
    memory: 16384
    vcpus: 8
    disk_size: 100
    volumes:
      - name: fast-data.qcow2
        size: 500
        path: /mnt/nvme/libvirt/high-performance-vm-fast-data.qcow2

Notes:

  • Default pool is always created
  • Custom pools are created in addition to the default
  • All pools autostart automatically
  • SELinux contexts applied automatically
  • Ownership based on path (/home → user, others → root)

See host_vars/storage_pools_examples.yml.example for complete examples.

Network Configuration

VMs can be configured with multiple network interfaces, each with custom MAC addresses and attached to different virtual networks.

Basic network configuration

By default, if no networks parameter is specified, VMs are created with a single NIC attached to the default libvirt network with an auto-generated MAC address.

Single network interface

vms:
  - name: myvm
    memory: 4096
    vcpus: 4
    disk_size: 50
    networks:
      - name: default

Single network with custom MAC address

vms:
  - name: myvm
    memory: 4096
    vcpus: 4
    disk_size: 50
    networks:
      - name: default
        mac: "52:54:00:11:22:33"

Multiple network interfaces

vms:
  - name: myvm
    memory: 4096
    vcpus: 4
    disk_size: 50
    networks:
      - name: default
        mac: "52:54:00:11:22:01"
      - name: storage-network
        mac: "52:54:00:aa:bb:01"
      - name: management-network
        mac: "52:54:00:cc:dd:01"

Network configuration options

Each network in the networks list can have:

Parameter Required Description
name No Virtual network name (default: "default")
mac No MAC address (auto-generated if not specified)

Note: MAC addresses must be unique across all VMs and follow the format XX:XX:XX:XX:XX:XX. The prefix 52:54:00 is commonly used for KVM virtual machines.

Creating virtual networks

Before using custom networks, ensure they exist in libvirt:

# List existing networks
virsh net-list --all

# Define a new network from XML
virsh net-define /path/to/network.xml

# Start the network
virsh net-start storage-network

# Set network to autostart
virsh net-autostart storage-network

Example network XML (storage-network.xml):

<network>
  <name>storage-network</name>
  <bridge name='virbr1'/>
  <forward mode='nat'/>
  <ip address='192.168.100.1' netmask='255.255.255.0'>
    <dhcp>
      <range start='192.168.100.2' end='192.168.100.254'/>
    </dhcp>
  </ip>
</network>

Playbooks

This project includes several playbooks for different aspects of VM management:

setup_libvirt.yml

Initial setup of libvirt on hosts. Installs packages, configures services, sets up storage pools, and configures permissions.

# Setup all hosts
ansible-playbook -i inventory setup_libvirt.yml

# Setup specific host
ansible-playbook -i inventory setup_libvirt.yml -l hostname

# Only install packages
ansible-playbook -i inventory setup_libvirt.yml --tags packages

manage_host_storage.yml

Standalone storage pool, directory, and ISO management. Can be used to create, update, or reconfigure storage independently of VM operations, and download ISO images for VM installation.

# Setup storage for all hosts
ansible-playbook -i inventory manage_host_storage.yml

# Setup storage for specific host
ansible-playbook -i inventory manage_host_storage.yml -l hostname

# Only create directories
ansible-playbook -i inventory manage_host_storage.yml --tags directories

# Only configure storage pool
ansible-playbook -i inventory manage_host_storage.yml --tags pool

# Only download ISOs
ansible-playbook -i inventory manage_host_storage.yml --tags iso

# Setup everything (storage + ISOs)
ansible-playbook -i inventory manage_host_storage.yml

Features:

  • Creates storage directories with proper permissions
  • Handles both /var/lib and /home user paths
  • Sets SELinux contexts (virt_image_t)
  • Creates and activates libvirt storage pools
  • Can rebuild pools if paths change
  • Downloads ISO images from URLs with optional checksum verification
  • Manages ISO file permissions and ownership
  • Idempotent downloads (won't re-download existing files)

ISO Configuration:

Define ISOs to download in host_vars:

iso_images:
  - url: "https://download.fedoraproject.org/pub/fedora/linux/releases/43/Server/x86_64/iso/Fedora-Server-dvd-x86_64-43-1.6.iso"
    alias: "fedora43x86.iso"
  - url: "https://releases.ubuntu.com/22.04/ubuntu-22.04.3-live-server-amd64.iso"
    alias: "ubuntu-22.04-server.iso"
    checksum: "sha256:abc123..."  # Optional

ISO parameters:

  • url: Direct download URL for the ISO image (required)
  • alias: Filename to save as in libvirt_storage_path (required)
  • checksum: Optional checksum for verification (format: "algorithm:hash")

See host_vars/iso_examples.yml.example for complete examples.

manage_host_network.yml

Virtual network management for libvirt. Create, configure, or destroy virtual networks with support for NAT, isolated (host-only), and bridge modes.

# Create networks from host_vars
ansible-playbook -i inventory manage_host_network.yml

# Create networks for specific host
ansible-playbook -i inventory manage_host_network.yml -l hostname

# List all networks
ansible-playbook -i inventory manage_host_network.yml --tags list

# Destroy specific network
ansible-playbook -i inventory manage_host_network.yml -e "network_name=storage-network" --tags destroy

Supported Network Types:

  • NAT: Network with outbound connectivity via NAT, isolated from physical network
  • Isolated: Host-only network, VMs can communicate with each other and host only
  • Bridge: Direct connection to physical network via existing bridge interface

Features:

  • Define networks in host_vars with custom IP ranges
  • DHCP configuration with optional static assignments
  • Automatic network startup and autostart configuration
  • Support for multiple networks per host
  • Network templates for each type

Network Configuration Example:

networks:
  - name: storage-network
    type: nat
    bridge: virbr1
    ip: 192.168.100.1
    netmask: 255.255.255.0
    dhcp_start: 192.168.100.10
    dhcp_end: 192.168.100.254
    autostart: true
    dhcp_hosts:  # Optional static DHCP
      - mac: "52:54:00:aa:bb:01"
        name: storage-node-1
        ip: 192.168.100.11

  - name: management-network
    type: isolated
    bridge: virbr2
    ip: 192.168.200.1
    netmask: 255.255.255.0
    dhcp_start: 192.168.200.10
    dhcp_end: 192.168.200.254
    autostart: true

  - name: external-bridge
    type: bridge
    bridge: br0  # Must exist on host
    autostart: true

See host_vars/network_examples.yml.example for complete examples.

Volume Configuration

VMs can be configured with multiple disk volumes beyond the primary OS disk. This is useful for database servers, storage nodes, or any scenario requiring separate data volumes.

Basic volume configuration

By default, every VM is created with a single primary disk specified by vm_disk_size_gb. This becomes the vda device.

Single VM with additional volumes

vms:
  - name: database-server
    memory: 8192
    vcpus: 4
    disk_size: 50  # Primary OS disk (vda)
    volumes:       # Additional data volumes
      - name: data01.qcow2
        size: 100  # Size in GB
      - name: data02.qcow2
        size: 200

Multiple volumes with custom configuration

vms:
  - name: storage-server
    memory: 4096
    vcpus: 2
    disk_size: 40
    volumes:
      - name: storage01.qcow2
        size: 500
        device: vdb  # Optional: specify device name
        format: qcow2  # Optional: disk format
      - name: storage02.qcow2
        size: 500
        device: vdc
      - name: logs.qcow2
        size: 50
        path: /home/jeyoung/libvirt/custom/logs.qcow2  # Optional: custom path
        device: vdd

Volume configuration options

Each volume in the volumes list can have:

Parameter Required Description
name Yes Volume filename (e.g., data01.qcow2)
size Yes Size in GB
device No Device name (vdb, vdc, etc.) - auto-assigned if not specified
format No Disk format (qcow2, raw, etc.) - defaults to qcow2
path No Full path to volume - defaults to <storage_pool>/<vm_name>-<name>

Notes:

  • The primary OS disk (vm_disk_size_gb) is always created as vda
  • Additional volumes are automatically assigned vdb, vdc, vdd, etc. in order
  • Volume paths default to: <storage_pool>/<vm_name>-<volume_name>
    • Example: /home/jeyoung/libvirt/images/database-server-data01.qcow2
  • You can override device assignment and paths as needed
  • All volumes inherit the storage pool path unless path is explicitly specified

Complete example with volumes and networks

vms:
  - name: database-cluster-1
    memory: 16384
    vcpus: 8
    disk_size: 50
    autostart: true
    networks:
      - name: default
        mac: "52:54:00:10:00:01"
      - name: storage-network
        mac: "52:54:00:20:00:01"
    volumes:
      - name: postgres-data.qcow2
        size: 200
        device: vdb
      - name: postgres-wal.qcow2
        size: 50
        device: vdc
      - name: backups.qcow2
        size: 500
        device: vdd

See host_vars/volumes_examples.yml.example for complete examples.

ISO Mount Configuration

VMs can be created with ISO images mounted as CDROM devices. This is useful for OS installation from ISO or providing additional installation media.

Basic ISO mount

Mount an ISO from the storage path:

vms:
  - name: fedora-install
    memory: 4096
    vcpus: 2
    disk_size: 50
    iso: "fedora43x86.iso"  # Filename from libvirt_storage_path

ISO with full path

Specify a full path to the ISO file:

vms:
  - name: custom-install
    memory: 4096
    vcpus: 2
    disk_size: 40
    iso: "/home/jeyoung/libvirt/iso/ubuntu-22.04-server.iso"

Complete installation example

VM configured for OS installation with ISO, multiple networks, and data volumes:

vms:
  - name: database-install
    memory: 16384
    vcpus: 8
    disk_size: 50
    iso: "fedora43x86.iso"
    autostart: false  # Don't autostart during installation
    networks:
      - name: default
        mac: "52:54:00:10:00:10"
      - name: storage-network
        mac: "52:54:00:20:00:10"
    volumes:
      - name: data01.qcow2
        size: 200
      - name: data02.qcow2
        size: 200

ISO mount behavior

When vm_iso is specified:

  • Boot order: CDROM first, then hard disk
  • Device assignment: ISO mounted as sda on SATA bus (read-only)
  • Disk devices: Regular disks still use virtio (vda, vdb, etc.)
  • Path resolution:
    • Filename only (e.g., "fedora43x86.iso") → looked up in libvirt_storage_path
    • Absolute path (e.g., "/home/user/custom.iso") → used as-is

Installation workflow

  1. Download ISO (if not already present):

    ansible-playbook -i inventory manage_host_storage.yml --tags iso

  2. Create VM with ISO mounted:

    ansible-playbook -i inventory manage_host_vms.yml --skip-tags configure

  3. Install OS via virt-manager console or VNC

  4. After installation, remove ISO and redefine VM:

    • Edit host_vars file, remove the iso: line
    • Redefine VM: ansible-playbook -i inventory manage_host_vms.yml --tags vm-create
    • Or manually eject via virt-manager

Tips:

  • Set autostart: false during installation to prevent automatic boot before setup
  • Use --skip-tags configure when creating installation VMs
  • ISOs must exist before VM creation (download first with manage_host_storage.yml)

See host_vars/iso_mount_examples.yml.example for complete examples.

manage_host_vms.yml

Unified VM creation and configuration. Handles both single VMs (command-line) and multiple VMs (inventory-based).

# Create VMs from host_vars
ansible-playbook -i inventory manage_host_vms.yml

# Create single VM
ansible-playbook -i inventory manage_host_vms.yml -e "vm_name=myvm"

# Create VMs for specific host
ansible-playbook -i inventory manage_host_vms.yml -l hostname

# Only create VMs (skip configuration)
ansible-playbook -i inventory manage_host_vms.yml --skip-tags configure

# Only configure existing VMs
ansible-playbook -i inventory manage_host_vms.yml --tags configure

Features:

  • Unified logic for single and multiple VMs
  • Architecture-aware (x86_64 and ARM64/aarch64)
  • UEFI firmware support for ARM64
  • Multiple network interfaces
  • Multiple disk volumes with custom configuration
  • Custom MAC addresses
  • Automatic VM configuration after creation
  • Waits for IP address assignment

reset_host.yml

DESTRUCTIVE: Removes all VMs, networks, and storage from a host. Use with caution!

# Reset specific host (REQUIRED)
ansible-playbook -i inventory reset_host.yml -l hostname

# Reset all hosts (requires confirmation)
ansible-playbook -i inventory reset_host.yml --extra-vars "confirm_reset_all=yes"

# Only remove VMs
ansible-playbook -i inventory reset_host.yml -l hostname --tags vms

# Only remove networks
ansible-playbook -i inventory reset_host.yml -l hostname --tags networks

# Only remove storage
ansible-playbook -i inventory reset_host.yml -l hostname --tags storage

Safety Features:

  • Requires explicit host limit or confirmation
  • 5-second warning pause before execution
  • Clear display of what will be removed
  • Summary of removed and remaining resources

What it removes:

  • All VMs (destroys running VMs, removes definitions and NVRAM)
  • All custom networks (preserves default network)
  • All storage pools
  • Storage directories and VM disk images
  • NVRAM firmware files
  • Temporary VM definition files

Advanced Usage

Using tags to run specific tasks

# Only setup packages
ansible-playbook -i inventory setup_libvirt.yml --tags packages

# Only create VM disks
ansible-playbook -i inventory manage_host_vms.yml --tags disk

# Only start VMs
ansible-playbook -i inventory manage_host_vms.yml --tags start

Debugging

Run with verbose output:

ansible-playbook -i inventory setup_libvirt.yml -vvv

Check facts from host:

ansible -i inventory libvirt_hosts -m setup | grep -i virt

Verify nested virtualization

Intel CPUs:

cat /sys/module/kvm_intel/parameters/nested

AMD CPUs:

cat /sys/module/kvm_amd/parameters/nested

Troubleshooting

Permission denied errors

Ensure your user is in the libvirt group:

sudo usermod -aG libvirt $USER
newgrp libvirt

Nested virtualization not enabled

For Intel:

sudo modprobe -r kvm_intel
sudo modprobe kvm_intel nested=1

For AMD:

sudo modprobe -r kvm_amd
sudo modprobe kvm_amd nested=1

To make permanent, create /etc/modprobe.d/kvm.conf:

options kvm_intel nested=1
# or for AMD:
options kvm_amd nested=1

VM fails to get IP address

Check libvirt network:

virsh net-list
virsh net-dumpxml default

Restart libvirt:

sudo systemctl restart libvirtd

SSH connection issues

Verify VM is running:

virsh list

Get VM IP:

virsh domifaddr <vm_name>

Check console:

virsh console <vm_name>

Contributing

Feel free to submit issues and enhancement requests!

License

This project is open source and available under the MIT License.

References