Change your block storage volume type

Knowledge Base

Change your block storage volume type


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Objective

The purpose of this guide is to show you how to change a block storage volume type from Classic or High speed to High speed gen2.

Requirements


OVHcloud Control Panel Access


Instructions

When trying to change a block storage volume type to a "High speed gen2" one, the migration policy will need to be changed from Never to On-demand.

The migration policy is set by default to Never as the volume stays on the same CEPH cluster. However, for the "High speed gen2" type, the volume will need to be migrated to a new cluster.

This modification can be made via Horizon or the OpenStack CLI.

If the block storage volume is attached to an instance, you must first detach it before proceeding. For more information, see the Detach a volume section of the guide "How to create and configure an additional disk on an instance".

Changing the volume type (retyping) via the OVHcloud Control Panel or the OVHcloud API is available only for unencrypted volumes. Encrypted volumes of type -LUKS cannot be retyped using these interfaces.

Retyping is supported via OpenStack / Horizon only for -LUKS to -LUKS volumes. In this case, volume restoration after retyping is not possible.

Conversions from -LUKS to non -LUKS (or vice versa) are not supported, including via OpenStack / Horizon.

Click on Block Storage in the left-hand menu under Storage & Backup.

Locate the relevant volume in the list, then click the ... button on the right. Select Change the volume type.

A new window opens, displaying the available volume types. Select the desired type, then confirm by clicking Edit.

Changing the volume type (retyping) may take a few minutes.

Log in to the Horizon interface and make sure you are in the correct region. You can verify this in the top left corner.

Region selection

Next, click on the Volumes menu on the left side and click on Volumes. Click on the drop-down arrow next to Edit Volume and select Change Volume Type.

Option selection

In the pop-up window, click on the drop-down menu under Type and select high-speed-gen-2. Next, click on the drop-down arrow under Migration Policy, and select On Demand.

Once done, click on Change Volume Type to confirm the change.

Option selection

Make sure to consult the following guide before proceeding:

First, list the type of volumes available in your region with the following command:

#~$ openstack volume type list
+--------------------------------------+----------------------------------------------------+-----------+
| ID                                   | Name                                               | Is Public |
+--------------------------------------+----------------------------------------------------+-----------+
| 27844ef7-1a9a-4944-be59-6e4eb19a71f6 | high-speed-gen2                                    | True      |
| 23f75fef-d4f6-416a-a884-95aa3fd45695 | classic                                            | True      |
| 2f78e8af-93c9-4e5c-b177-83c4a7ec456a | high-speed                                         | True      |
| 9c5b1e42-3d8f-4a67-a9d2-84f3b2e7c1aa | high-speed-gen2-luks                               | True      |
| f41d7c8e-6a2b-4b91-9e73-2d6c0a58e94f | classic-luks                                       | True      |
| c8e92a5d-0f6e-4e3b-b1a4-7a9d6f3c2e8b | high-speed-luks                                    | True      |
---------------------------------------------------------------------------------------------------------

Please note that if the "high-speed-gen2" or -LUKS volume types do not appear in the list, it means that they are not available in this region.

-LUKS volume types are only displayed when they are supported in the region and compatible with the volume's encryption type.

Next, switch volume types with the following command:

$ openstack volume set --type <VOLUME_TYPE> --retype-policy on-demand <VOLUME_NAME_OR_ID>

Go further

To learn how to migrate a Block Storage volume to an encrypted LUKS volume, check out our dedicated guide: Migrating a Block Storage volume to an encrypted LUKS volume.

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