concept hypervisor in category openstack
This is an excerpt from Manning's book OpenStack in Action.
In the following subsections, you’ll see the details related to specific resource components: server virtualization, via the control of hypervisors; networking, via the control of vendor-provided hardware and OpenStack services; block and object storage, via the control of vendor and OpenStack services. Finally, we’ll look at OpenStack services in relation to common cloud terms. As you’ll see, OpenStack is a framework that coordinates resources and services, regardless of the underlying technology vendor.
A hypervisor or virtual machine monitor (VMM) is software that manages the emulation of physical hardware for virtual machines. OpenStack is not a hypervisor, but it does control hypervisor operations. Many hypervisors are supported under the OpenStack framework, including XenServer/XCP, KVM, QEMU, LXC, ESXi, Hyper-V, BareMetal, and others (see the hypervisor support matrix: https://wiki.openstack.org/wiki/HypervisorSupportMatrix). You’re likely familiar with VMware ESX, VMware ESXi, and Microsoft Hyper-V, which at the current time are the dominant hypervisors in enterprise virtualization space. Because of licensing restrictions, cost, and other factors, there has been less OpenStack community support for commercial hypervisors than for open source alternatives.
Figure 1.5 shows OpenStack managing resources that are virtualized by a hypervisor on physical hardware. OpenStack coordinates the management of many hypervisor resources and virtual machines in an OpenStack cluster.
