Best Practices and Recommendations for Handling Unallocated Storage on Azure Virtual Desktops (AVDs)

Question

Description of Issue:

We have observed that additional storage purchased or selected during the creation of Azure Virtual Desktops (AVDs) is not automatically allocated to any drive. This has led to challenges in utilizing the extra storage effectively, as it remains unallocated.

Details:

Our preferred solution is to extend the C: drive with the unallocated space. However, there are some obstacles and concerns with this approach:

Partition Structure:

The unallocated storage on our AVD instances is separated from the C: drive by a 666 MB recovery partition (partition 5), making the unallocated space non-contiguous to C. Due to this layout, we are unable to extend C: to include this additional storage.

Recovery Partition:

We would like clarification on whether this recovery partition (partition 5) is actively used by AVDs. Is there any guidance or recommendation from Microsoft regarding the deletion or relocation of this recovery partition?

Impact on Azure Virtual Desktops:

In the event that extending C: becomes technically feasible by modifying or removing the recovery partition, we are concerned about any potential impacts on active AVDs. Could extending C: on an already deployed and in-use AVD cause issues? Are there any best practices Microsoft recommends in such scenarios?

Future Deployments and Disk Allocation:

Looking ahead, we would like to streamline this process. Is there an option or setting that can automatically allocate additional storage to C: upon initial deployment of AVDs, preventing unallocated storage from arising in the first place?

Current AVD Configuration Details:

Source Image Publisher: microsoftwindowsdesktop

Source Image Offer: windows-11

Source Image Plan: win11-23h2-ent

VM Size: Standard D8as v5 (8 vCPUs, 32 GiB memory)

Disk Type and Size: Standard SSD LRS, 512 GiB

We appreciate any guidance Microsoft can provide on best practices for managing unallocated storage in AVD environments, as well as any specific recommendations for extending C: or handling the recovery partition.

Thank you for your assistance.

Answer 1

Hi Fabian Quist,

Welcome to Microsoft Q&A, thanks for posting your query.

You are facing challenges with additional storage purchased for Azure Virtual Desktops (ADVs) not being automatically to any drive, leaving it as unallocated space. You want to extend the C: drive with this unallocated space, but a recovery partition is stopping you from doing it. You are looking for a clarification on what is the role of recovery partition. Here are the key points

1. Extending the C: drive:

Extending the C: drive to include unallocated space that's separated by the recovery partition is not simple. You would typically need disk management tools to remove the recovery partition, which can be risky. Modifying the recovery partition on an active AVD could impact system stability and loss of recovery options. So, it is generally not recommended to make such changes on production systems without thoroughly tested them.

2. Recovery Partition:

The recovery partition is typically used for system recovery and troubleshooting. It contains tools and files necessary for restoring the operating system. While the recovery partition is generally not available during the normal operations, it is best to keep the recovery partition as it is, unless you have a very good reason to remove it. Altering or deleting this partition could lead to issue if it is necessary to restore the system.

3. Managing Unallocated Storage:

Unless it is absolutely necessary, avoid deleting or moving the recovery partition. Instead, consider using the unallocated space for additional data drives. If you cannot extend the C: drive, consider creating the additional data drives for data storage. This makes the effective use of unallocated space without altering the system partition.

Regular monitor the storage usage and planning for future storage need it is also important best practices to avoid running into similar issues in the future.

4. Future Deployments and Disk Allocation:

Currently, Azure does not provide a build-in feature to automatically allocate additional storage to the C: drive during the ADV deployment.

you can consider this approach.

• Automation Scripts: Use Azure Automation or Azure CLI scripts to manage storage settings post-deployment, ensuring any extra storage is allocated effectively. Automatically setting disk sizes and types during deployment. This approach can streamline and standardize the setup process, helping to avoid issues with unallocated storage in new deployments.
• Custom Images: Build a custom image that includes the desired C: drive configuration and use it in future AVD deployments.

Reference:

https://learn.microsoft.com/en-us/azure/virtual-desktop/

https://learn.microsoft.com/en-us/azure/virtual-desktop/create-custom-image-templates

While it is technically possible to extend the C: drive by modifying the recovery partition, it is not recommended due to issues. Instead, consider using the unallocated space for additional data drives or creating custom images for future deployments.

 

Please let us know if you have any further queries. I’m happy to assist you further. 

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