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By default, a VM that is not allocated is not billed. But if you had used certain resources attached to in the VM, such as a public IP or external volume, these may still be a part of the your cloud resources, and they may be billed.
The user can go to the VM icon of a not allocated VM and edit the VM configuration. And the user can deploy the VM again. If they deploy the VM again, then the VM will start with a new copy of the disk from the catalogue.
To save a new copy of the VM disk to the catalogue, create an Abiquo instance template from the VM.
If your VMs were captured from a hypervisor and you want to undeploy and deploy them again, then you should make an instance template before you undeploy. You can then recreate the VM from the instance template.
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