VDI virtual machines
Virtual machines are created using volume snapshots. This make new VMs spawn quickly, because there are no volume data copied from source to target volume.
Note, that you will have to provide copy-on-write capable storage (like Ceph) to Glance and Cinder services.
VDI structure consists of 4 virtual machine types:
- Source VM
- Initial VM
- VDI VM
- VDI-ephemeral VM
Source VMs are created from Glance image (if using Ceph and Glance API v2, volume will be also created via snapshot). - This is your primary VM, into which you should install all needed software.
Note: Ceph does not support copy-on-write on QCOW images, so please make sure, that you upload RAW images to Glance service
Initial VM is a snapshot for Source VM - this machine should be used to run Sysprep scripts.
VDI VM is a VDI virtual machine - client will be provided with a running VM from its snapshot.
VDI-ephemeral VM - VM which will be provided to client, this is a temporary machine, created from its parent VDI VM and which will be destroyed and rebuilt by OpenStack broker each time user disconnects from it (after $return_to_pool_after period). This machine is invisible in KVM-VDI dashboard.
Block diagram for VM creation order:
