> For the complete documentation index, see [llms.txt](https://helpcenter.xopero.com/xopero-one-en/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://helpcenter.xopero.com/xopero-one-en/backup-and-recovery/virtual-machines/vmware/backup/unsupported-disk-types.md).

# Unsupported disk types

**When performing a virtual machine backup (agentless), Xopero ONE relies on the hypervisor's snapshot mechanism to ensure data consistency. Certain disk types are architecturally excluded from snapshots by the hypervisor itself, which means they cannot be included in a standard VM-level backup.**

***

## Excluded VMware disks

The following disk modes do not support snapshots and cannot be backed up:

* **Independent persistent** — changes are written immediately to the disk, but the disk does not participate in snapshots.
* **Independent non-persistent** — changes are discarded when the VM is powered off or reset; these disks also do not support snapshots.

{% hint style="info" %}
This is not a limitation of **Xopero ONE**, but a characteristic of how these virtual disks are designed to operate within **VMware** and **Hyper-V** environments. Because a snapshot cannot be created, **Xopero ONE** cannot guarantee data consistency or access data during a host-level task.
{% endhint %}

***

## Recommended workaround

If you need to protect data on independent disks, you can use the following method:

1. Install the **Xopero ONE Backup\&Recovery Agent** directly within the virtual machine’s guest operating system.
2. Configure a file or image-level backup task with the installed agent.

By using an in-guest agent, **Xopero ONE** utilizes the internal VSS (**Windows**) or live-read (**Linux**) mechanisms to capture the data, effectively bypassing the hypervisor's snapshot limitations.


---

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