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Each of the life cycle operation is a workflow resulting in either provisioning or deleting multiple CloudStack resources. There is no guarantee a workflow of a life cycle operation will succeed due to the lack of 2PC like model a two-phase-commit model, by means of resource reservation followed by provisioning semantics. Also there is no guarantee of a rollback succeeding. For instance, while provisioning a cluster of 10 VMs, deployment may run out of capacity to provision any more VMs after provisioning the first five Vms. In which case as rollback action, the provisioned VMs can be destroyed. But there can be cases where deleting a provisioned VM is not possible temporarily. For instance when a host is disconnected etc. So its not possible to achieve strong consistency and this will not be a focus in this phase of the development.

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