Nova - the compute orchestrator

The Nova service is the heart of the OpenStack cloud. It is a collection of daemons that work to orchestrate availability of compute resources, leveraging virtualization features that have been running on Linux machines for years! Rather than reinventing the wheel, Nova works with a variety of existing hypervisor technologies, including QEMU-KVM, QEMU, Hyper-V, VMware ESXi, Xen, and XenServer. It also supports the ability to leverage existing Linux container technologies such as LXC and Docker. When one boots an instance, Nova leverages available CPU, memory, and disk resources on compute nodes. In a production OpenStack environment, a customer may have anywhere from five to 5,000 compute nodes hosting virtual machine instances.

Nova architecture

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