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VM Quick install

Debian 13, Ubuntu 24.04 LTS

Packages

debian 13 need to boot from UEFI so you need to install ovfm package on your hypervisor.

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sudo apt install ovfm

Rapid deployment with cloud-img

1️⃣ Download a Cloud Image

cloud-init is already installed on those generic images (not on nocloud images).

Get a debian cloud image:

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wget https://cloud.debian.org/images/cloud/trixie/latest/debian-13-generic-amd64.qcow2

Then copy image to /var/lib/libvirt/images:

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sudo cp debian-13-generic-amd64.qcow2 /var/lib/libvirt/images/debian-13-generic-amd64.qcow2

2️⃣ Create user-data and meta-data

This user-data file creates a user named locadmin:

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hostname: testvm
manage_etc_hosts: true
disable_root: false
chpasswd:
  list: |
    root:password
  expire: False

users:
  - name: ansible
    gecos: Ansible User
    groups: sudo
    shell: /bin/bash
    sudo: ["ALL=(ALL) NOPASSWD:ALL"]
    ssh_authorized_keys:
      - ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIGboh8qF6vDcZMLoU+54r+RvZv6smo6rH7N4LnaL0ULZ benoit@ymir

package_update: true
package_upgrade: true
packages:
  - python3
  - python3-apt
  - qemu-guest-agent
  - git

ssh_deletekeys: true
ssh_genkeytypes: ['rsa', 'ecdsa', 'ed25519']


runcmd:
  - systemctl enable --now qemu-guest-agent

timezone: Europe/Paris

Create meta-data:

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instance-id: testvm01
local-hostname: testvm

3️⃣ Create the Cloud-Init ISO

Combine both into an ISO image for the VM:

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genisoimage -output seed.iso -volid cidata -joliet -rock user-data meta-data

(cloud-localds from cloud-utils can also do this, but genisoimage works everywhere - so ok on the hypervisor.)

Then move this seed.iso image to /var/lib/libvirt/images/:

sudo mv seed.iso /var/lib/libvirt/images/seed.iso

4️⃣ Create the VM with virt-install

Here’s a working example using virt-install:

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sudo virt-install \
  --name testvm \
  --memory 2048 \
  --vcpus 2 \
  --disk path=/var/lib/libvirt/images/testvm01-debian13.qcow2,backing_store=/var/lib/libvirt/images/debian-13-generic-amd64.qcow2,size=10 \
  --disk path=/var/lib/libvirt/images/seed.iso,device=cdrom \
  --os-variant debian13 \
  --import \
  --network network=nat,model=virtio \
  --network network=br0,model=virtio \
  --virt-type kvm \
  --graphics none \
  --boot uefi  \
  --noautoconsole

Notes:

  • --import skips installation since the image already has an OS.
  • The backing_store pattern creates a copy-on-write (COW) layer so you don’t modify the base image.
  • The seed.iso injects your cloud-init config, so can be kept among all VMs created.
  • The qemu-guest-agent helps with IP reporting, shutdowns, etc.

Remove VM

To Remove VM, use:

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sudo virsh destroy testvm
sudo virsh undefine testvm --nvram
sudo rm /var/lib/libvirt/images/testvm01-debian13.qcow2