Creating Virtual Machines

PaaS Cloud supports traditional virtual machines powered by KubeVirt. VMs are defined by two separate resources: a vm-disk (storage) and a vm-instance (compute). This guide walks you through creating and accessing a VM using the dashboard or virtctl.

Prerequisites

• Active MetaCentrum membership
• Logged into Chloe Dashboard
• Sufficient tenant quota for CPU, memory, and disk
• (Optional) virtctl installed for CLI access. See Using virtctl.

VM Resources Overview

Step 1: Create a vm-disk

Before creating a VM instance, you need a disk from which the VM will boot. Disk can be also cloned from already existing instance.

From a Golden Image

Select a pre-built OS image from the dashboard:

source:
  image:
    name: ubuntu

Available golden image names correspond to Cozystack instance profiles (e.g., ubuntu, debian, almalinux, windows.2k22). See VM Instance Types for the full list.

From an HTTP URL

Download an image from a remote URL:

source:
  http:
    url: "https://download.cirros-cloud.net/0.6.2/cirros-0.6.2-x86_64-disk.img"

Upload a Local Image

Create an empty disk for upload:

source:
  upload: {}

After the disk is created, the dashboard provides a virtctl image-upload command. See VM Image Upload for details.

Empty Disk

Create an empty disk to attach to a VM (e.g., for a secondary data volume):

source: {}

Optional: CD-ROM

Mark a disk as an optical drive:

optical: true

Step 2: Create a vm-instance

After the disk is ready, create the VM instance.

Required Fields

• disks — List of disks to attach. The first disk is always bootable.

  disks:
  - name: example-system
  - name: example-data

• instanceType — A predefined hardware template. Default is u1.medium.
  • Examples: u1.micro, u1.medium, cx1.2xlarge, m1.2xlarge, rt1.medium
  • See VM Instance Types for the full catalog.
• instanceProfile — A guest OS preference that configures KubeVirt defaults.
  • Examples: ubuntu, debian, almalinux, windows.11, windows.2k22
• instanceName — A name for the instance.

Optional Fields

• sshKeys — List of SSH public keys for authentication (injected via cloud-init).
• cloudInit — Cloud-init user data for custom provisioning.
• networks — Networks to attach the VM to. If empty, a default tenant network is used.
• external — Enable external access from outside the cluster (true / false).
• externalPorts — Ports to forward externally when external is enabled. Default is [22].
• gpus — List of GPU resources to attach for GPU passthrough.

Example YAML

apiVersion: cozystack.io/v1alpha1
kind: VMInstance
metadata:
  name: my-vm
spec:
  instanceType: u1.medium
  instanceProfile: ubuntu
  disks:
  - name: my-vm-system
  sshKeys:
  - "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAI..."
  external: true
  externalPorts:
  - 22
  - 80
  - 443

Step 3: Access the Virtual Machine

Dashboard Console

• Open the VM details in the dashboard.
• Click Console for a browser-based VNC or serial console session.

virtctl (CLI)

# Serial console
virtctl console <vm-name>

# VNC
virtctl vnc <vm-name>

# SSH (requires external access or a jump host)
virtctl ssh <user>@<vm-name>

Default users usually match the OS name (e.g., ubuntu for Ubuntu, debian for Debian, almalinux for AlmaLinux).

Lifecycle Actions

• Start / Stop / Restart — Use the action menu in the VM list or details page. Under the hood, this changes the KubeVirt runStrategy (Always, Halted, RerunOnFailure).
• Resize — Change the instanceType (e.g., from u1.medium to u1.large) when the VM is stopped. This modifies CPU and memory allocations.
• Snapshot — Create a point-in-time snapshot of a vm-disk for recovery.
• Delete — Remove the vm-instance and optionally its vm-disk resources. Back up data first.

Next Steps

• VM Image Upload — Upload custom OS images.
• Using virtctl — Full CLI reference for VM operations.
• Exposing Services — Publish VM services externally.
• Monitoring and Logs — Observe VM metrics and logs.