Virtual Machine Template

A provider-agnostic representation of a template for a virtual machine.

A VirtualMachineTemplate allows the HobbyFarm platform to schedule resources across multiple providers while providing a common definition for content creators. It is a required resource for creating an Environment.

A VM template represents a potential VM configuration, with its implementation varying by provider. For instance, AWS might interpret the template as a t3.medium, while Azure might implement it as a Standard_D2_v2.

Each Environment is responsible for determining the specific realization of a VirtualMachineTemplate.

Kubernetes Commands

The following commands are useful for managing VirtualMachineTemplate resources in Kubernetes.

## Get a list of all VirtualMachineTemplates
kubectl get virtualmachinetemplates -n hobbyfarm-system

## Create a VirtualMachineTemplate from a YAML manifest
kubectl apply -f {virtualMachineTemplateManifest} -n hobbyfarm-system

## Edit a VirtualMachineTemplate
kubectl edit virtualmachinetemplate {virtualMachineTemplateName} -n hobbyfarm-system

## Backup a VirtualMachineTemplate to a YAML manifest
kubectl get virtualmachinetemplate {virtualMachineTemplateName} -n hobbyfarm-system -o yaml > {virtualMachineTemplateManifest}

## Delete a VirtualMachineTemplate
kubectl delete virtualmachinetemplate {virtualMachineTemplateName} -n hobbyfarm-system

Example VirtualMachineTemplate Manifest

The following shows an example of a VirtualMachineTemplate manifest in Kubernetes.

apiVersion: hobbyfarm.io/v1
kind: VirtualMachineTemplate
metadata:
  name: vmt-neuc2clbtv
  namespace: hobbyfarm-system
spec:
  config_map:
    cloud-config: ""
    image: ubuntu-20-04-x64
    size: s-1vcpu-512mb-10gb
    ssh_username: root
    webinterfaces: '[]'
  image: ubuntu-20-04-x64
  name: do-ubuntu-20-04-x64

Configuration

`name`

Display name for the VM template.

`image`

Default value for the image to use when provisioning this VM.

Acceptable values will depend upon the provisioner in use. Useful either as a default value for a default provisioner, or when multiple environments use the same provisioner. Can be overridden via configuration in the Environment resource.

`config_map`

The ConfigMap provides the ability to customize more values given to the provisioner. Useful if the provisioner can distinguish between regions or different sizing options.

An example for a config_map for virtual machines on Hetzner could look the following

## Example Hetzner config_map
spec:
  config_map:
    server_type: cx21   ## Hetzner has available sizings cx11, cx21, cx31 ...
    ssh_username: root  ## Default SSH Username is root
    location: nbg1      ## Region

Cloud-Init configuration

VirtualMachineTemplates may offer Cloud-Init configuration. Currently this is saved under the cloud-config key inside the config_map.

## Example Cloud-Init configuration
spec:
  config_map:
    cloud_config: |
      runcmd:
        - echo "Hello World"

NOTE: Future releases of HobbyFarm will allow the Cloud-Init configuration to be saved in it’s own field inside the VirtualMachineTemplate or a ConfigMap.

Services and Webinterfaces

Services and webinterfaces can be configured for VMTs. A Service may provide a webinterface on a specific port and path which will be shown to the user in an iFrame. This webinterface will be proxied to ensure authorization. Currently this should be configured through the UI as it is stored in an array under the webinterfaces key inside the config_map. You can define presets of often used services using PredefinedServices.