Creating a Template VM from a qcow2 image

This document outlines the general procedure for adding new Template VMs in vSphere for .qcow2 images.

The template VM in this guide refers to a regular vSphere VM and not VM Templates according to the vSphere terminology. The difference is quite subtle, but VM Templates are not supported yet by machine-controller.

Prerequisites

  • vSphere (tested on version 6.7)
  • govc (tested on version 0.37.2)
  • qemu-img (tested on version 4.2.0)
  • curl or wget

Procedure

  1. Download the guest image in qcow2 format end export an environment variable with the name of the file.

    # The URL below is just an example
image_url="https://cloud.centos.org/centos/7/images/CentOS-7-x86_64-GenericCloud.qcow2"
image_name="$(basename -- "${image_url}" | sed 's/.qcow2$//g')"
curl -sL "${image_url}" -O .

  2. Convert it to vmdk e.g.

    qemu-img convert -O vmdk -o subformat=streamOptimized "./${image_name}.qcow2" "${image_name}.vmdk"

  3. Upload to vSphere using WebUI or GOVC:

    Make sure to replace the parameters on the command below with the correct values specific to your vSphere environment.

    govc import.vmdk -dc=dc-1 -pool=/dc-1/host/cl-1/Resources -ds=ds-1 "./${image_name}.vmdk"

  4. Inflate the created disk (see [VMware documentation][inflate_thin_virtual_disks] for more details)

    govc datastore.disk.inflate -dc dc-1 -ds ds-1 "${image_name}/${image_name}.vmdk"

  5. Create a new virtual machine using that image with vSphere WebUI.

  6. During the Customize Hardware step:

    1. Remove the disk present by default
    2. Click on ADD NEW DEVICE, select Existing Hard Disk and select the disk previously created.

  7. The vm is ready to be used by the MachineController by referencing its name in the field .spec.template.spec.providerSpec.value.cloudProviderSpec.templateVMName of the MachineDeployment.