Is it possible to remove a Template that was used to deploy a Guest with Thin Provisioning

Solution Verified - Updated -

Environment

Red Hat Enterprise Virtualization (RHEV) 3.x

Issue

  • A Guest was deployed with thin provisioning from a template.
  • Is it possible to remove a Template that used to deploy a Guest with Thin Provisioning.

Resolution

  • If you don't want the Guest to be based on the template images, you can set the "Template Provisioning" parameter to "Clone" in the "Resource Allocation" tab when creating a new Guest. With the 'Clone' setting, the Guest images will create a new image which will not be based on the template images.

  • For a deployed thin provisioned Guest based on a template, create a snapshot of the Guest and clone a new Guest from the snapshot. The original template now can removed with shutting down and removing thin provisioned Guest that was created using original template. You can also export the template and thin provisioned Guest to export domain as backup.

Root Cause

  • A template cannot be removed without shutting down and removing the thin provisioning Guest that were created using that template.

  • If a Guest is created using thin provisioning from a template, then the disks of the created Guest are based on the volumes of the template images using qcow, and therefore, they will be linked to the template.

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