OpenStack Nova Compute Service

Nova is the compute scheduler and instance lifecycle manager for OpenStack. It receives instance creation requests, selects an appropriate hypervisor through the scheduler and placement service, coordinates with Glance for images, Neutron for networking, and Cinder for volumes, then manages the full instance lifecycle through libvirt/KVM.

Nova operates in a cell-based architecture. Cell0 holds instances that failed to schedule. Cell1 (and beyond) holds running instances. The placement service tracks resource inventories (vCPUs, RAM, disk) independently from Nova, providing accurate capacity data for scheduling decisions.

Deploy

Kolla-Ansible Configuration

globals.yml settings:

# Hypervisor type
nova_compute_virt_type: "kvm"        # Production: hardware KVM
# nova_compute_virt_type: "qemu"     # Nested virt or no VT-x/AMD-V

# Libvirt container
enable_nova_libvirt_container: "yes"