Increase the size of a cloud boot-from-volume server system disk

  • Last updated on: 2019-01-29
  • Authored by: Rackspace Community

If you have a cloud boot-from-volume server that is reaching its capacity limit, you can increase the size of the volume without building a new virtual machine (VM), or adding disks that give you alternate storage points, rather than adding to your existing limit.

This article shows you how to detach the boot volume, clone it to a larger size, and then swap the volumes out and boot the VM.

Shut off the VM

Before you detach the volume that contains the operating system (OS), you need to shut off the VM.

To perform this action, use Secure Shell (SSH) and Remote Desktop (RDP) to log in to the server, then shut it down by using its respective shutdown method.

After you shut off the server, it displays in the Rackspace Cloud Control Panel as Shutoff.

Detach the volume from the VM

You cannot detach the volume from the VM by using the Cloud Control Panel. You detach it by using an application programming interface (API) call. We have developed the Pitchfork tool to make this process easier for you.

Use the following steps to detach the volume from the VM:

  1. In your browser, go to the Pitchfork home page.
  2. Log in to Pitchfork at the top right by using the username and API key that you use to log in to the Cloud Control Panel.

    Note: To learn how to obtain your API key, see View and reset your API key.

  3. After you are logged in to Pitchfork, select Cloud Servers.
  4. Scroll to the Volumes section. Next to List Attached Volumes, click GET.
  5. In the server_id field, paste the universally unique identifier (UUID) of your VM and click Send API Call.

    The response is similar to the following example:

        "volumeAttachments": [
                "device": "/dev/xvda",
                "serverId": "0123abcd-1988-4eva-bad2-dabone987",
                "id": "e5c9b775-13fe-4a1c-8f25-a2af8a99a381",
                "volumeId": "e5c9b775-13fe-4a1c-8f25-a2af8a99a381"
  6. Record the value that is returned in the id field. While this value is usually the same as the volumeId, we recommend that you verify that this is the case.

  7. Next, use the following steps to detach the volume by using the Pitchfork API call Unattach Volume From Server:

    1. Click DELETE.
    2. Enter the UUID of your server and the id from the response to the previous API call.
    3. Click Send API Call to detach the volume.

The volume disappears from the Volumes list on the Cloud Server Details page for your VM.

Size up the volume by cloning a larger version

Use the following steps to size up the volume:

  1. In the Cloud Control Panel, click Select a Product > Rackspace Cloud.

  2. In the top navigation bar, select Storage > Block Storage Volumes.

  3. Find the volume that was the system disk for your server.

    Note: It might have a name similar to System disk for 0123abcd-1988-4eva-bad2-dabone987, or the name might be something unique.

  4. Click the gear icon next to the volume, then select Clone Volume.

  5. In the window that appears, enter the Name, Region, Type, and Size that you want to use for the cloned volume, then click Clone Volume.

When the volume is ready, you receive a notification, and the status bar to the left of the volume name on the Block Storage Volumes page displays as green.

Attach the new volume to the VM

Use the following steps to attach the new volume to the VM:

  1. In Pitchfork, use the API call Attach Volume To Server.
  2. Click POST.
  3. Enter the UUID of the server, the UUID of the new volume, and the UUID of the dev_assignment that you want to specify for /dev/xvda.
  4. Click Send API Call.

In the Cloud Control Panel, you see that the volume is attached to your server, which still displays as Shutoff.

Restart the VM

In the Cloud Control Panel, run the Reboot command.

After the VM is in Active status, you are able to log in to the VM again by using SSH and RDP or the Emergency Console.

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