# Flavorless VM Support

Although using flavors to create virtual machines is a fundamental feature of <code class="expression">space.vars.product\_name</code>, many organizations—especially those moving away from traditional virtualization vendors—may prefer a simpler process that doesn’t require specifying a flavor when creating a VM.

## Zero-Size Flavor

To support this scenario, Private Cloud Director allows creation of VMs using a **special zero-size flavor**, where both the **number of vCPUs and the RAM are set to zero**. Private Cloud Director ships out of the box with one such flavor, but you can also create new flavors where the number of vCPUs and the RAM are set to zero.

When you choose such a flavor when creating a new VM, you can then specify the amount of CPU and Memory that the VM should get provisioned with.

Using the zero-size flavor is a requirement in order to use CPU or memory hot-add feature

## Create a Zero-Size Flavor

1. In the Private Cloud Director UI, navigate to Virtual Machines ▷ Flavors and click Create Flavor.
2. **Enable Hot-plug**: toggle **on**.
3. Set a Disk size.
4. *(Optional)* Add Metadata if you want Private Cloud Director to place VMs on specific host aggregates.
5. Check the Make Public checkbox if you would like to make this flavor available to all tenants.
6. Click Create Flavor.

## Deploy a VM with a Zero-Size Flavor

1. Go to Virtual Machines ▷ Virtual Machines and click Deploy New VM.
2. During Flavor selection: enable the **Hot-add Compatible** toggle to filter the list.
3. Choose the zero-size flavor you created above.
4. In the Hotplug RAM (MB) and Hotplug vCPUs fields, enter the initial resources you would like to create this VM with. Maximum values are automatically configured by the system.
5. Finish the remaining steps and deploy the VM.

Private Cloud Director will create the VM with the requested CPU and Memory resources.

## Hot-add CPU or Memory to a Running VM

Read [VM Hot-Add CPU Or Memory](https://platform9.com/docs/private-cloud-director/2025.8/private-cloud-director/cpu-memory-hot-add-support) about how to hot add resources to a running VM.

## Use Flavorless VM with CLI

To automate creation of flavorless VM using CLI, API or terraform provider, use the zero-size flavor when creating the VM and use the following values for the metadata fields.

{% tabs %}
{% tab title="Bash" %}

```bash
{
    "HOTPLUG_MEMORY": "<specify memory in MB for the VM>",
    "HOTPLUG_CPU": "<specify number of VCPUs for the VM>"
}
```

{% endtab %}
{% endtabs %}

## Limitations & Best Practices

* VM disk size **cannot** be changed via the hot-add feature.


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